Sheet supply device and sheet supply method

ABSTRACT

A controller includes: an adhesion member position determination unit that determines a position of an adhesion member in a rotation direction of a roll on the basis of the result of detection from an adhesion member detector in a state in which the roll has been rotated by a shaft control unit; and an outer diameter determination unit that determines an outer diameter of the roll in a portion where the adhesion member is positioned, the determination being performed on the basis of the result of detection from an outer diameter detector in a state in which driving of shaft drive sources are controlled by the shaft control unit such that the adhesion member is positioned within a detection range of the outer diameter detector on the basis of the position of the adhesion member determined by the adhesion member position determination unit.

TECHNICAL FIELD

The present invention relates to a sheet supply device for continuouslysupplying a sheet from a roll around which the sheet is wound.

BACKGROUND ART

Conventionally, for example, a supply device described in PatentLiterature 1 has been known. The supply device includes a first supplyshaft that holds a first roll, a second supply shaft that holds a secondroll, and a joining mechanism that joins a sheet of the second roll to asheet of the first roll when the remaining quantity of sheet on thefirst roll is equal to or less than a preset remaining quantity.

The joining mechanism includes a shaft drive source that rotatablydrives the second supply shaft, a tape detector that detects a positionof an adhesive tape in a rotation direction of the second roll, theadhesive tape being provided on an outer peripheral surface of thesecond roll for bonding the sheet of the first roll, an outer diameterdetector that detects an outer diameter of the second roll, and a spliceroll that presses the sheet of the first roll against the outerperipheral surface of the second roll.

The supply device described in Patent Literature 1 operates as followsby controlling the driving of the joining mechanism.

When the remaining quantity of sheet on the first roll is equal to orless than a preset remaining quantity in a state in which the sheet onthe first roll is supplied, the outer diameter of the second roll isdetected by the outer diameter detector. Next, the second supply shaftis rotated by the shaft drive source such that a speed of the outerperipheral surface of the second roll is the same as a conveyance speedof the sheet supplied from the first roll. In this state, the positionof the adhesive tape in the rotation direction is detected by a rotationposition detector, and the sheet on the first roll is pressed againstthe outer peripheral surface of the second roll by the splice roll onthe basis of the result of detection.

Thereby, the sheet of the second roll is joined to the sheet suppliedfrom the first roll via the adhesive tape, and the sheet of the firstroll is cut at an upstream side of the joining position, so the supplyof the sheet of the second roll can be started without stopping thesupply of the sheet from the first roll.

In the supply device described in Patent Literature 1, the reason whythe outer diameter of the second roll is detected by the outer diameterdetector is not specified, but it is considered that the outer diameterof the second roll is detected to specify the pressing position(position of the outer peripheral surface of the second roll in a radialdirection) of the sheet of the first roll by the splice roll.

Here, a thickness of a sheet may vary in a longitudinal direction due tofactors such as a method for manufacturing a sheet or a sheet may bedeformed in a thickness direction depending on a type of sheets. Inaddition, winding of a relatively soft material such as a non-wovenfabric around a roll may be loose and uneven, or the soft material maybe deformed by a load applying to a part in a rotation direction. Inthese cases, the second roll may have different outer diameters at eachposition in the rotation direction (the second roll may be warped).

In the supply device described in Patent Literature 1, the outerdiameter of the second roll is measured before the rotation of thesecond supply shaft, and it is not clear at which position in therotation direction of the second roll the outer diameter of the secondroll is measured. Therefore, the pressing position of the sheet on thefirst roll in the radial direction cannot be accurately specified, andit may be difficult to reliably join the sheets.

CITATION LIST Patent Literature

Patent Literature 1: JP H09-12185 A

SUMMARY OF INVENTION

An object of the present invention is to provide a sheet supply deviceand a sheet supply method capable of reliably joining a sheet of a firstroll to a sheet of a second roll even when the second roll is warped.

In order to solve the above problems, the present invention provides asheet supply device for supplying a sheet from a first roll and a secondroll around which the sheet is wound, the sheet supply device including:a first support shaft that supports the first roll at a center positionthereof; a second support shaft that supports the second roll at acenter position thereof; a joining mechanism that joins the sheet of thesecond roll to the sheet of the first roll; and a controller thatcontrols driving of the joining mechanism such that the sheet of thefirst roll is joined to the sheet of the second roll when a remainingquantity of the sheet of the first roll is equal to or less than apreset remaining quantity in a state in which the sheet of the firstroll is supplied, in which the joining mechanism includes a second shaftdrive source that rotatably drives the second support shaft, an adhesionmember detector that detects a position of an adhesion member providedon an outer peripheral surface of the second roll in a rotationdirection of the second roll, an outer diameter detector that detects anouter diameter of the second roll, and a pressing mechanism that pressesthe sheet of the first roll against the adhesion member of the secondroll, and the controller includes a shaft control unit that controlsdriving of the second shaft drive source such that the second roll isrotated, an adhesion member position determination unit that determinesthe position of the adhesion member in the rotation direction of thesecond roll on the basis of a result of detection from the adhesionmember detector in a state in which the second roll is rotated by theshaft control unit, and an outer diameter determination unit thatdetermines the outer diameter of the second roll in a portion where theadhesion member is positioned on the basis of the result of detectionfrom the outer diameter detector in a state in which the position of theadhesion member determined by the adhesion member position determinationunit is positioned within a detection range of the outer diameterdetector, and the controller controls the driving of the pressingmechanism such that the sheet of the first roll is pressed against theadhesion member of the second roll on the basis of the outer diameter ofthe second roll determined by the outer diameter determination unit.

In addition, the present invention provides a sheet supply method forsupplying a sheet from a first roll and a second roll around which thesheet is wound, the sheet supply method including: a first supply stepof supplying the sheet of the first roll supported at a center positionby a first support shaft; and a joining step of joining the sheet of thesecond roll to the sheet of the first roll using a joining mechanismthat joins the sheet of the second roll to the sheet of the first rollwhen a remaining quantity of the sheet of the first roll is equal to orless than a preset remaining quantity in a state in which the sheet ofthe first roll is supplied, in which the joining mechanism includes asecond shaft drive source that rotatably drives the second supportshaft, an adhesion member detector that detects a position of anadhesion member provided on an outer peripheral surface of the secondroll in a rotation direction of the second roll, an outer diameterdetector that detects an outer diameter of the second roll, and apressing mechanism that presses the sheet of the first roll against theadhesion member of the second roll, and in the joining step, theposition of the adhesion member in the rotation direction of the secondroll is determined on the basis of a result of detection from theadhesion member detector in a state in which the second roll is rotatedby the second shaft drive source, the outer diameter of the second rollin a portion where the adhesion member is positioned is determined onthe basis of the result of detection from the outer shape detector in astate in which the determined position of the adhesion member ispositioned within a detection range of the outer diameter detector, andthe sheet of the first roll is pressed against the adhesion member ofthe second roll by the pressing mechanism on the basis of the determinedouter diameter of the second roll.

According to the present invention, even when the second roll is warped,the sheet of the first roll can be reliably joined to the sheet of thesecond roll.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a partial front cross-sectional view of a sheet supply device1 according to an embodiment of the present invention.

FIG. 2 is a plan view of the sheet supply device 1 of FIG. 1.

FIG. 3 is a side view of the sheet supply device 1 of FIG. 1.

FIG. 4 is a rear view of the sheet supply device 1 of FIG. 1.

FIG. 5 is a plan cross-sectional view of a support mechanism in a statein which a support shaft supporting a standby side roll is disposed at asplice position.

FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5.

FIG. 7 is a partial side cross-sectional view showing a moving unit apart of which is omitted.

FIG. 8 is a schematic front view of a joining mechanism showing apositional relationship among a pressing roller, a cutter, a first guideroller, a second guide roller, a third guide roller, and an urgingmechanism.

FIG. 9 is a schematic view showing a blade edge shape of a rotary blade.

FIG. 10 is a front view showing a process in which the support shaftsupporting the standby side roll in FIG. 1 is rotated toward a spliceposition.

FIG. 11 is a front view showing a state in which the support shaftsupporting the standby side roll shown in FIG. 1 is disposed at thesplice position.

FIG. 12 is a partially enlarged front view showing a state in which themoving unit is disposed at a position corresponding to a detectableposition.

FIG. 13 is a partially enlarged front view showing a state in which themoving unit is disposed at a control switching position.

FIG. 14 is a partially enlarged front view showing a state in which themoving unit is disposed at an advance position.

FIG. 15 is a front view showing a state after a sheet of a supply sideroll is cut.

FIG. 16 is a front view showing a state in which the sheet is wound bythe support shaft supporting the supply side roll.

FIG. 17 is a front view showing a state in which a support shaftdifferent from the support shaft shown in FIG. 1 is disposed at amounting position.

FIG. 18 is a block diagram showing an electrical configuration of acontroller.

FIG. 19 is a flowchart showing a process executed by the controller ofFIG. 18.

FIG. 20 is a flowchart showing the process executed by the controller inFIG. 18.

FIG. 21 is a flowchart showing the process executed by the controller inFIG. 18.

FIG. 22 is a flowchart showing the process executed by the controller inFIG. 18.

FIG. 23 is a partially enlarged front view showing an urging mechanismaccording to another embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described withreference to the accompanying drawings. The following embodiments arespecific examples of the present invention and do not limit thetechnical scope of the present invention.

FIG. 1 is a partial front cross-sectional view of a sheet supply device1 according to an embodiment of the present invention. FIG. 2 is a planview of the sheet supply device 1 of FIG. 1. FIG. 3 is a side view ofthe sheet supply device 1 of FIG. 1. FIG. 4 is a rear view of the sheetsupply device 1 of FIG. 1. Hereinafter, a horizontal direction in FIG. 1will be described as an X direction, a vertical direction in FIG. 1 willbe described as a Z direction, and a direction orthogonal to the Xdirection and the Z direction will be described as a Y direction.

Referring to FIGS. 1 to 3, the sheet supply device 1 is for supplyingsheets from rolls R1 and R2 around which the sheets are wound.

Specifically, the sheet supply device 1 includes a base 2, a supportmechanism 3 that supports the rolls R1, R2 while being attached to thebase 2, a joining mechanism 4 that joins one sheet of one of the rollsR1 and R2 supported by the support mechanism 3 to the other sheet whilebeing attached to the base 2, and a controller 5 that controls anoperation of the support mechanism 3 and the joining mechanism 4.

The base 2 includes a mounting plate 2 a mounted on a predeterminedmounting surface, two columns 2 b that stands on the mounting plate 2 aso as to face each other in the X direction, two columns 2 c that faceseach other in the X direction at a position away from the two columns 2b in the Y direction, a beam 2 d that extends in the X direction whilebeing fixed to upper end portions of the two columns 2 b, a beam 2 ethat extends in the X direction while being fixed to upper end portionsof the two columns 2 c, shaft support parts 2 f and 2 g (see FIG. 3)that stand on the beams 2 d and 2 e, respectively, and two rails 2 h and2 i that extend in the X direction on the beams 2 d and 2 e. FIG. 1 is apartial front cross-sectional view in a state in which a part of themounting plate 2 a is cut away such that the illustration of the twocolumns 2 b and the beams 2 d are omitted.

The shaft support parts 2 f and 2 g face each other in the Y directionon one side (right side in FIG. 1) of the beams 2 d and 2 e in the Xdirection, while the rails 2 h and 2 i face each other in the Ydirection on the other side (left side in FIG. 1) of the beams 2 d and 2e in the X direction.

The support mechanism 3 is attached to the shaft support parts 2 f and 2g of the base 2 so as to be rotatable about a rotation shaft 3 aextending in the Y direction.

Specifically, the support mechanism 3 includes a rotation member 3 bthat is rotatably attached to the base 2 about the rotation shaft 3 a,support shafts 3 c and 3 d that support the rolls R1 and R2 at centerpositions thereof, respectively, while being provided on the rotationmember 3 b, a rotating guide member 3 e that is rotatably attached tothe base 2 about the rotation shaft 3 a together with the rotationmember 3 b, and adjacent guide members 3 f and 3 g that are providedadjacent to the support shafts 3 c and 3 d, respectively. The base 2 andthe support mechanism 3 described above constitute a shaft support unitthat supports the support shafts 3 c and 3 d.

The rotation member 3 b extends between the beams 2 d and 2 e of thebase 2 in a direction orthogonal to the rotation shaft 3 a. In FIGS. 3and 4, a part of the rotation member 3 b is omitted.

The support shafts 3 c and 3 d are provided at positions away from therotation shaft 3 a in the rotation member 3 b in a direction orthogonalto the rotation shaft 3 a. Specifically, the support shaft 3 c isprovided at one end portion of the rotation shaft 3 a in the rotationmember 3 b, while the support shaft 3 d is provided at the other endportion of the rotation shaft 3 a in the rotation member 3 b. Inaddition, the support shafts 3 c and 3 d extend from the rotation member3 b to one side (beam 2 d side) in the Y direction. As described above,the support shafts 3 c and 3 d are supported in a cantilever manner withrespect to the rotation member 3 b. Therefore, a worker can easily mountthe rolls R1, R2 from near sides of free ends of the support shafts 3 cand 3 d such that the free ends of the support shafts 3 c and 3 d areinserted into centers of the rolls R1, R2.

Here, the rotation member 3 b is rotatably supported by the base 2between a state in which one of the support shafts 3 c and 3 d isdisposed at a mounting position and a state in which the one of thesupport shafts 3 c and 3 d is disposed at a splice position.Hereinafter, the mounting position and the splice position will bedescribed.

<Mounting Position>

In the state in which a sheet is supplied from the roll R1 supported byone (support shaft 3 c in FIG. 1) of the support shafts 3 c and 3 d, therotation member 3 b is rotated in a state in which the other supportshaft 3 d is disposed at the mounting position (position shown inFIG. 1) for mounting a new roll on the other support shaft 3 d.

<Splice Position>

The rotation member 3 b is rotated counterclockwise in FIG. 1 from themounting position, and the rotation member 3 b is rotated until thesupport shaft 3 d is disposed at the splice position shown in FIG. 11via the position shown in FIG. 10. In this state, a center of therotation shaft 3 a and a center of the support shaft 3 d disposed at thesplice position are disposed in parallel on the same horizontal plane.FIG. 2 is a plan view of the sheet supply device 1 in a state in whichthe support shaft 3 d is disposed at the splice position.

At the splice position, when the sheet of the roll R1 is joined to thesheet of the roll R2 by the joining mechanism 4 described later, thesupply of the sheet from the roll R2 is started, and the rotation member3 b is rotated clockwise from this state. As a result, as shown in FIG.17, the support shaft 3 c that supports the roll R1 is disposed at theabove-described mounting position. As described above, the rotationmember 3 b is rotated forward and backward such that each of the supportshafts 3 c and 3 d repeatedly moves from the mounting position to thesplice position, and as a result, the sheets are sequentially suppliedfrom the rolls R1 and R2 supported by the support shafts 3 c and 3 d.

Further, the support mechanism 3 includes a member drive mechanism thatrotatably drives the rotation member 3 b as described above, and a shaftdrive mechanism that rotatably drives the support shafts 3 c and 3 d.Hereinafter, the member drive mechanism and the shaft drive mechanismwill be described with reference to FIGS. 4 and 5. FIG. 5 is a plancross-sectional view of the support mechanism 3 in a state in which thesupport shaft 3 d is disposed at the splice position.

Specifically, the rotation drive mechanism includes a pulley 3 h fixedto the rotation shaft 3 a, and an endless belt 3 i hung on the pulley 3h. The endless belt 3 i is hung on a pulley fixed to a rotation shaft ofa rotation member drive source (motor) 2 j fixed to the column 2 c ofthe base 2. When the rotation shaft of the rotation member drive source2 j is rotated, power of the rotation member drive source 2 j istransmitted to the rotation shaft 3 a via the endless belt 3 i, and therotation shaft 3 a is rotated.

The shaft drive mechanism includes an inner pulley 3 j that is attachedto an outer side of the rotation shaft 3 a in a state where the innerpulley 3 j is rotatable about the rotation shaft 3 a with respect to therotation shaft 3 a, an outer pulley 3 k that is attached to an outerside of the pulley 3 j in a state where the outer pulley 3 k isrotatable about the rotation shaft 3 a with respect to the pulley 3 j, afirst inner endless belt 3 l and a second inner endless belt 3 m thathang on the inner pulley 3 j, and a first outer endless belt 3 n and asecond outer endless belt 3 o that hang on the outer pulley 3 k. Thefirst inner endless belt 3 l hangs on a pulley fixed to a rotation shaftof a shaft drive source (motor) 4 k that is fixed to the beam 2 e of thebase 2, and the first outer endless belt 3 n hangs on a pulley fixed toa rotation shaft of a shaft drive source (motor) 4 l that is fixed tothe beam 2 e of the base 2. In addition, the second inner endless belt 3m hangs on a pulley fixed to the support shaft 3 d, and the second outerendless belt 3 o hangs on a pulley fixed to the support shaft 3 c. Whenthe rotation shafts of the shaft drive sources 4 k and 4 l rotate, powerof the shaft drive sources 4 k and 4 l is transmitted to the supportshafts 3 c and 3 d via the endless belts 3 l to 3 o, and the supportshafts 3 c and 3 d rotate. In addition, since the inner pulley 3 j andthe outer pulley 3 k are attached to the rotation shaft 3 a in a statewhere the inner pulley 3 j and the outer pulley 3 k are rotatable withrespect to the rotation shaft 3 a, thereby the power of the shaft drivesources 4 k and 4 l can be transmitted to the support shafts 3 c and 3 dregardless of the rotating operation of the rotation shaft 3 a.

Referring to FIGS. 1 to 3, the rotating guide member 3 e and theadjacent guide members 3 f and 3 g each are for preventing a sheet of aroll (in FIG. 1, roll R1: hereinafter, the roll that is supplying thesheet is referred to as the supply side roll), which is supplying thesheet, of the rolls R1 and R2 from coming into contact with the otherroll (in FIG. 1, roll R2: hereinafter, the roll other than the supplyside roll are referred to as the standby side roll) when the supportshafts 3 c and 3 d are rotated from the mounting position (see FIG. 1)to the splice position (see FIG. 11).

Specifically, the rotating guide member 3 e includes a pair of holdingplates 3 p and 3 q that are fixed to the rotation shaft 3 a whileextending in a direction intersecting the rotation member 3 b and guiderollers 3 r and 3 s that are attached to both end portions of theholding plates 3 p and 3 q in the longitudinal direction. The holdingplates 3 p and 3 q are fixed to the rotation shaft 3 a in a state wherethe holding plates 3 p and 3 q are away from each other in the Ydirection (see FIG. 2) so as to be disposed on both sides of the sheetson the rolls R1 and R2 in the Y direction. The guide rollers 3 r and 3 sare attached to the holding plates 3 p and 3 q in a state where theguide rollers 3 r and 3 s are rotatable about an axis along the Ydirection between the holding plates 3 p and 3 q.

In addition, each of the adjacent guide members 3 f and 3 g includes aholding member 3 t that extends from the rotation member 3 b and a guideroller 3 u that is attached to a tip of the holding member 3 t. Theholding member 3 t is provided on one side (beam 2 e side) of the rollsR1 and R2 in the Y direction. In addition, the holding member 3 t has abase end portion that extends from the rotation member 3 b to one sidein the rotation direction (counterclockwise direction) of the rotationmember 3 b, and a tip portion that extends outward in the radialdirection of the rotation shaft 3 a from the base end portion. The guideroller 3 u extends from the tip portion of the holding member 3 t to aposition on the other side (beam 2 d side) of the rolls R1 and R2 in theY direction, and is attached to the holding member 3 t in a state wherethe guide roller 3 u is rotatable about an axis along the Y direction.

When the rotation member 3 b is rotated and the sheets of the rolls R1and R2 come into contact with outer surfaces of the guide rollers 3 r, 3s, and 3 u, the sheets are guided downstream with the rotation of theguide rollers 3 r, 3 s, and 3 u.

In addition, the support mechanism 3 includes a discharge mechanism thatdischarges the rolls R1, R2 mounted on the support shafts 3 c, 3 d fromthe support shafts 3 c and 3 d. FIG. 6 is a cross-sectional view takenalong line VI-VI in FIG. 5. Although FIG. 6 shows the dischargemechanism provided on the support shaft 3 c, a similar dischargemechanism is also provided on the support shaft 3 d, and a descriptionof this discharge mechanism will be omitted.

Referring to FIG. 6, the discharge mechanism includes a discharge member3 v that is attached to the support shaft 3 c in a state in which thesupport shaft 3 c penetrates, and a push-pull mechanism 3 w (in thepresent embodiment, the number of push-pull mechanisms 3 w is two, butthe number of push-pull mechanisms 3 w may be one) that pushes and pullsthe discharge member 3 v against the rotation member 3 b. The push-pullmechanism 3 w has a main body that is fixed to the rotation member 3 b,and a displacement member that can be displaced in the Y direction withrespect to the main body, and is constituted by, for example, an aircylinder or a motor having a ball screw mechanism. The push-pullmechanism 3 w is configured to displace a non-discharge position wherethe displacement member is indicated by a solid line to a dischargeposition indicated by a two-dot chain line by receiving power orelectric power from a discharge drive source (for example, an air supplysource or a power supply: see FIG. 18) 2 k provided on the base 2. Thedischarge member 3 v moves in the Y direction as indicated by thetwo-dot chain line due to the displacement of the displacement member,and the roll R1 is pressed and discharged from the support shaft 3 c.

Referring to FIGS. 1 and 2, the joining mechanism 4 includes an outerdiameter detector 4 a that is fixed to the base 2, a moving unit (a partof the pressing mechanism) 4 b that is attached to the base 2 so as tobe movable in the X direction with respect to the base 2, a unit drivemechanism 4 c (see FIG. 4) that drives the moving unit 4 b, an adhesionmember detector 4 d, a pressing roller (a part of the pressingmechanism) 4 e, a cutter 4 f, a first guide roller 4 g (another guideroller), a second guide roller 4 h (guide roller), a third guide roller4 i, and an urging mechanism (see FIG. 8) 4 j that are attached tomoving unit 4 b, and the above-described shaft drive sources 4 k and 4 l(see FIG. 5).

The outer diameter detector 4 a detects the outer diameter of thestandby side roll (roll R2 in FIG. 11) disposed at the splice position,and is constituted by, for example, a laser sensor. The outer diameterdetector 4 a is fixed on the moving unit 4 b by a bracket 2 n that isprovided at a position opposite to the support mechanism 3 with respectto the moving unit 4 b in the two beams 2 d and 2 e so as to extendacross the two beams 2 d and 2 e of the base 2. In addition, a detectionaxis D1 (see the two-dot chained line in FIG. 11: trajectory throughwhich a center of a detection range passes from the outer diameterdetector 4 a to the roll: optical axis in the case of the laser sensor)of the outer diameter detector 4 a attached to the bracket 2 n isdisposed at the same position in the Y direction as a central line ofthe standby side roll (roll R2 in the case of FIG. 11) in a widthdirection (Y direction), and is disposed perpendicularly to a centralaxis (central axis of the support shaft) of the standby side roll (seeFIG. 11).

FIG. 7 is a partial side cross-sectional view showing the moving unit 4b a part of which is omitted. In FIG. 7, the second guide roller 4 h andthe third guide roller 4 i are omitted.

The moving unit 4 b includes a moving plate 4 r that is provided on thetwo beams 2 d and 2 e of the base 2, a pair of sliders 4 s that is fixedto both end portions of the moving plate 4 r in the Y direction, a pairof detector brackets 4 m that stands on the moving plate 4 r so as toface each other in the Y direction, a revolution member 4 n that isprovided so as to extend across the two detector brackets 4 m, a pair ofroller support members 4 o that stands on the moving plate 4 r so as toface each other in the Y direction between the two detector brackets 4m, and a pair of brackets 4 p that extends downward from a lower surfaceof the moving plate 4 r so as to face each other in the Y direction.

The pair of sliders 4 s is engaged with the rails 2 h and 2 i of thebeams 2 d and 2 e, respectively. Thereby, the moving plate 4 r, that is,the moving unit 4 b can move in the X direction along the rails 2 h and2 i with respect to the base 2. As shown in FIGS. 1 and 3, the portions(mounting plates 2 a, columns 2 b and 2 c, beams 2 d and 2 e, rails 2 hand 2 i) that extend from the shaft support parts 2 f and 2 g to themoving unit 4 b side in the base 2 correspond to a unit support partwhich has the moving unit 4 b movably attached thereto and is mounted ona preset mounting surface. As shown in FIG. 1, the support shaft(support shaft 3 d in FIG. 1) disposed at the mounting position isdisposed in an area other than the area overlapping with the shaftsupport parts 2 f and 2 g and the unit support part in a side viewviewed along the rotation shaft 3 a.

Referring to FIGS. 4 and 7, the unit drive mechanism 4 c that drives themoving plate 4 r in the X direction are provided on each of the beam 2 dand beam 2 e of the base 2. Since these unit drive mechanisms 4 c havethe same configuration, only the unit drive mechanism 4 c provided onthe beam 2 e will be described below. The unit drive mechanism 4 cincludes an endless belt 4 c 1 that is fixed to the moving plate 4 r, aplurality of pulleys 4 c 2 that are provided on the beam 2 e of the base2 and has the endless belt 4 c 1 hanging thereon, and a unit drivesource (servomotor, detector drive source, a part of the pressingmember) 4 c 3 that is provided on the column 2 c of the base 2. The unitdrive source 4 c 3 has a rotation shaft (no reference numeral) on whichthe endless belt 4 c 1 hangs via the pulley. The plurality of pulleys 4c 2 circularly hold the endless belt 4 c 1 such that a part of theendless belt 4 c 1 extends along the X direction, and the moving plate 4r is fixed to a part of the endless belt 4 c 1 extending in the Xdirection. When the unit drive source 4 c 3 is rotated in one direction,the power of the unit drive source 4 c 3 is transmitted via the endlessbelt 4 c 1, and the moving plate 4 r advances toward the supportmechanism 3, while when the unit drive source 4 c 3 is rotated in areverse direction, the moving plate 4 r retracts in a direction awayfrom the support mechanism 3. As described above, the moving plate 4 radvances and retracts in the X direction by the unit drive mechanism 4c.

The pair of roller support members 4 o provided on the moving plate 4 rare attached with the pressing roller 4 e that presses the sheet of thesupply side roll (roll R1 in FIG. 11) against the outer peripheralsurface of the standby side roll (roll R2 in FIG. 11) in response to thedriving of the unit drive mechanism 4 c. The pressing roller 4 e isdisposed between the two roller support members 4 o, and is rotatablyattached to the two roller support members 4 o about the axis along theY direction.

In addition, in a state in which one (roll R2 in FIG. 14) of the rollsR1 and R2 is disposed at the splice position, the rotation shaft 3 a,the support shaft 3 d, and the pressing roller 4 e are attached to thebase such that the center of the rotation shaft 3 a, the center of thesupport shaft 3 d, and the center of the pressing roller 4 e aredisposed in parallel with each other on the same horizontal plane. Inthis state, the unit drive mechanism 4 c moves (advances) the movingunit 4 b in the horizontal direction, and as a result, the pressingroller 4 e moves in the radial direction of the roll R2 such that thecenter of the pressing roller 4 e moves on a straight line passingthrough the center of the rotation shaft 3 a and the center of thesupport shaft (support shaft 3 d in FIG. 11) disposed at the spliceposition, and the pressing roller 4 e is pressed against the roll R2. Asdescribed above, the pressing roller 4 e is pressed against a position(hereinafter, referred to as a pressing position P1) intersecting astraight line connecting between the center of the rotation shaft 3 a,the center of the support shaft 3 d, and the center of the pressingroller 4 e on the outer peripheral surface of the roll (roll R2 in FIG.14) that is disposed at the splice position by the unit drive mechanism4 c.

The moving unit 4 b supports the pressing roller 4 e (is attached to thebase 2) such that the pressing roller 4 e can be approached to anddetached from the outer peripheral surface of the roll between anadvance position (an example of a proximity position: see FIG. 14) wherethe pressing roller 4 e is pressed against the pressing position P1 anda retracted position (see FIGS. 1 and 10) where the pressing roller 4 eis away from the pressing position P1. When the support shaft isdisposed at the splice position (see FIG. 11) in the state in which theassumed roll having the largest outer diameter is supported by thesupport shaft, the retracted position is a preset position as a positionwhere the moving unit 4 b and parts provided on the moving unit 4 b canavoid the contact with the roll.

Referring to FIGS. 4 and 7, the revolution member 4 n provided on themoving unit 4 b is attached to the pair of detector brackets 4 m in thestate where the revolution member 4 n is rotatable about the rotationshaft extending in the Y direction with respect to the pair of detectorbrackets 4 m. In addition, the moving unit 4 b is provided on the pairof detector brackets 4 m, and includes a revolution drive source (forexample, a motor) 4 q that applies power for rotating the revolutionmember 4 n to the revolution member 4 n.

The revolution member 4 n is attached with the adhesion member detector4 d that is constituted by, for example, a color sensor (for example, aline sensor or an area sensor) that can detect the position of anadhesion member H (see FIG. 12) in a rotation direction of a standbyside roll, the adhesion member H being provided on the outer peripheralsurface of the standby side roll. Here, the adhesion member H is amember (for example, double-sided tape) that is provided on the outerperipheral surface of the standby side roll, fastens an end of the sheeton the outer peripheral surface of the standby side roll, and permitsadhesion from the outer side of the sheet of the supply side roll.

The adhesion member detector 4 d is attached to the revolution member 4n such that a detection axis of the adhesion member detector 4 d isdisposed at the same position in the Y direction as the central line ofthe sheet of the standby side roll (R2 in FIG. 11) at the spliceposition (see FIG. 11) in the width direction (Y direction). Thedetection axis is a trajectory through which a midpoint of a detectionline from the line sensor to an object to be detected passes, in thecase of the line sensor, and a trajectory through which a center of animaging range from the area sensor to the object to be detected passes,in the case of the area sensor.

Further, the revolution member 4 n can revolve with respect to a rollersupport member 4 o between a detected position where the adhesion memberdetector 4 d is disposed between the pressing roller 4 e and the supportshaft 3 d such that a detection axis D2 of the adhesion member detector4 d is disposed perpendicularly with respect to the center of thesupport shaft 3 d, as shown in FIG. 12, and a retracted position wherethe adhesion member detector 4 d retracts from a position between thepressing roller 4 e and the support shaft 3 d, as shown in FIG. 13. Theretracted position is the position of the adhesion member detector 4 dset such that the distance from the adhesion member detector 4 d to thecenter of the support shaft 3 d is longer than the distance from thepressing roller 4 e to the center of the support shaft 3 d. Thedetection axis D2 of the adhesion member detector 4 d disposed at thedetected position is disposed at the same position as a straight line(see FIG. 14) connecting between the center of the rotation shaft 3 a,the center of the support shaft 3 d, and the center of the pressingroller 4 e in a front view.

FIG. 8 is a schematic front view of the joining mechanism 4 showing thepositional relationship among the pressing roller 4 e, the cutter 4 f,the first guide roller 4 g, the second guide roller 4 h, the third guideroller 4 i, and the urging mechanism 4 j. FIG. 8 shows a state in whichthe moving unit 4 b moves to the advance position and the pressingroller 4 e is pressed against the roll R2.

Referring to FIGS. 7 and 8, the pair of brackets 4 p is attached withthe first guide roller 4 g that guides the sheet drawn from the supplyside roll toward the pressing position P1 of the standby side roll (rollR8 in FIG. 8) disposed at the splice position. The first guide roller 4g is disposed between the two brackets 4 p, and is rotatably supportedby the two brackets 4 p about an axis along the Y direction. Further,the first guide roller 4 g is disposed at a position farther in the Xdirection from the roll (roll R2 in FIG. 8) disposed at the spliceposition than the pressing roller 4 e, and is disposed below thepressing roller 4 e. Thereby, as shown in FIG. 8, when the pressingroller 4 e is pressed against the roll, the first guide roller 4 gpresses a middle part of a sheet guided from the guide roller 3 s of thesupport mechanism 3 to the pressing position against the roll R2 side(support mechanism 3 side). As a result, the sheet is guided from thefirst guide roller 4 g to the pressing position P1 at an angle θ1 withrespect to a tangential line C1 to the outer peripheral surface of theroll at the pressing position P1.

In addition, the second guide roller 4 h and the third guide roller 4 iare attached to the roller support member 4 o shown in FIG. 7. The twoguide rollers 4 h and 4 i are each disposed between the two rollersupport members 4 o, and are rotatably supported to the two rollersupport members 4 o about the axis along the Y direction.

The second guide roller 4 h is disposed at a position farther in the Xdirection from the roll (roll R2 in FIG. 8) disposed at the spliceposition than the pressing roller 4 e, and is disposed above thepressing roller 4 e. Thereby, as shown in FIG. 8, the second guideroller 4 h changes a direction of a sheet downward at the second guideroller 4 h to guide the sheet downward, the sheet being guided obliquelyupward from the pressing position P1 to the second guide roller 4 h inthe state in which the pressing roller 4 e is pressed against the roll.Here, the sheet is guided from the pressing position P1 to the secondguide roller 4 h at an angle θ2 with respect to the tangential line C1to the outer peripheral surface of the roll at the pressing position P1.

Hereinafter, the disposition and functions of the first guide roller 4 gand the second guide roller 4 h will be described.

The second guide roller 4 h is disposed on an opposite side to the roll(roll R2 in FIG. 8) at the splice position based on the tangential lineC1 in the state where the pressing roller 4 e is pressed against thepressing position P1. In addition, the second guide roller 4 h guidesthe sheet such that the sheet is guided from the pressing roller 4 e ina direction away from the roll R2.

The first guide roller 4 g is disposed on the opposite side to the roll(roll R2 in FIG. 8) at the splice position based on the tangential lineC1, and on the opposite side to the second guide roller 4 h based on aplane including the pressing position P1 and the center of the pressingroller 4 e in the state in which the pressing roller 4 e is pressedagainst the pressing position P1. In addition, the first guide roller 4g guides the sheet such that the sheet is guided from the first guideroller 4 g to the pressing position P1 in a direction approaching theroll R2.

The angle θ2 between the sheet guided from the pressing position P1 tothe second guide roller 4 h and the tangential line C1 is greater thanthe angle θ1 between the sheet guided from the first guide roller 4 g tothe pressing position P1 and the tangential line. As described above,since the angle θ1 is set to be smaller than the angle θ2, a space forthe cutter 4 f can be secured on an opposite side of the standby sideroll R2 with respect to the sheet. In addition, since the angle θ1 isset to be smaller than the angle θ2, the guide roller 3 s that guidesthe sheet to the pressing position P1 can be disposed close to thetangential line C1, and the sheet supply device 1 can be configuredcompactly.

The third guide roller 4 i is disposed at a position closer to thetangential line C1 than the second guide roller 4 h is, on an oppositeside (upper side) of the first guide roller 4 g with respect to thepressing roller 4 e. As shown in FIG. 1, when one support shaft (supportshaft 3 d in FIG. 1) is disposed at the mounting position, the thirdguide roller 4 i is provided to apply tension to the sheet between thesupport shaft and one guide roller 3 u.

In addition, the cutter 4 f configured to be capable of cutting a sheetbetween the first guide roller 4 g and the pressing roller 4 e isattached to the pair of brackets 4 p. The cutter 4 f includes a shaft 4f 1 that is rotatably attached to both brackets 4 p about a shaftextending in the Y direction, a rotary blade 4 f 2 that extends in the Ydirection along the shaft 4 f 1 and is fixed to the shaft 4 f 1, cutterdriving means 4 f 3 that rotatably drives the rotary blade 4 f 2 aboutthe rotation shaft 4 f 1, and a cutter drive source 4 f 4 (see FIG. 18)that supplies air to the cutter driving means 4 f 3. The cutter drivingmeans 4 f 3 is constituted by an air cylinder that has a cylinder and arod that can be extended and retracted with respect to the cylinder. Inaddition, the cutter drive source 4 f 4 is constituted by a compressoror the like that supplies compressed air to the cutter driving means 4 f3. The cutter driving means 4 f 3 may be constituted by a motor having aball screw mechanism. In this case, the cutter drive source 4 f 4 may beconstituted by a power supply that supplies electric power to the motor.

The cutter 4 f is provided at a position (position opposite to the rollbased on the tangential line C1) away from the sheet in the X directionbetween the first guide roller 4 g and the pressing roller 4 e (that is,below the pressing roller 4 e). The cutter 4 f is attached to the movingunit 4 b in a state where the cutter 4 f is moveable (rotatable) betweena non-cutting position (position indicated by a solid line in FIG. 8)away from the sheet and a cutting position (position indicated by atwo-dot chain line in FIG. 8) for cutting the sheet. Specifically, therotary blade 4 f 2 rotated to the non-cutting position is disposed at aposition away from the sheet between the first guide roller 4 g and thepressing roller 4 e in the X direction, and a tip portion of the rotaryblade 4 f 2 rotated to the cutting position is disposed so as tointersect the sheet between the first guide roller 4 g and the pressingroller 4 e. In addition, the rotary blade 4 f 2 rotated to the cuttingposition takes a posture inclined downward with respect to a directionorthogonal to the sheet between the first guide roller 4 g and thepressing roller 4 e. Specifically, in the present embodiment, when anangle θ3 between the rotary blade 4 f 2 and the sheet is about 38°, thetip portion of the rotary blade 4 f 2 comes into contact with the sheet,but when the rotary blade 4 f 2 is further rotated from the contactposition toward the sheet by about 5° to about 15°, the sheet is easilycut. Specifically, when the angle θ3 rotates from the contact positionby about 10°, the sheet is most easily cut. As described above, thecutter 4 f cuts the sheet of the supply side roll R1 at a position belowthe center (the center of the support shaft 3 d) of the standby sideroll R2.

FIG. 9 is a schematic view showing the blade edge shape of the rotaryblade 4 f 2. As shown in FIG. 9, the rotary blade 4 f 2 has a pluralityof V-shaped blades arranged in the Y direction, and these blades piercethe sheet to cut the sheet.

Referring to FIGS. 7, 8, and 18, the urging mechanism 4 j is configuredto be switched between a supply state in which a force in a directionaway from the pressing position P1 is applied to a portion (hereinafter,referred to as a remaining portion) on an upstream side of the sheet inthe conveyance direction from the cutting position by the cutter in thesheet of the roll (for example, roll R2 in FIG. 8) disposed at thesplice position and a stop state in which the application of the forcestops.

Specifically, the urging mechanism 4 j includes an air nozzle 4 j 1 andan urging force generation source 4 j 2 (see FIG. 18) that suppliescompressed air to the air nozzle 4 j 1.

The air nozzle 4 j 1 has an outlet that blows out the compressed airsupplied from the urging force generation source 4 j 2. The outlet ofthe air nozzle 4 j 1 is disposed downward toward the guide roller 3 s ofthe support mechanism 3 so as to apply a force to the upstream side ofthe sheet in the conveyance direction based on the first guide roller 4g in the sheet in the state in which the pressing roller 4 e is pressedagainst the roll. In addition, the air nozzle 4 j 1 is detachablyattached to the moving plate 4 r of the moving unit 4 b by a bolt (notshown). Specifically, the air nozzle 4 j 1 is attached to the movingplate 4 r in the state in which a center position of the outlet of theair nozzle 4 j 1 in the Y direction coincides with a center position ofthe roller disposed at the splice position in the width direction (Ydirection). There are a plurality of types of rolls R1 and R2 havingdifferent width dimensions, and a plurality of screw holes (see FIG. 7:no reference numeral) are provided on the moving plate 4 r such that themounting position of the air nozzle 4 j 1 can be changed for each of theplurality of types of rolls R1 and R2. For example, the air nozzle 4 j 1can be attached to the moving plate 4 r at a position indicated by asolid line and two positions indicated by a two-dot chain line in FIG.7.

The compressed air blowing out from the outlet of the air nozzle 4 j 1attached in this way is blown to the guide roller 3 s through a positionopposite to the cutter 4 f of the first guide roller 4 g as indicated byan arrow A1 in FIG. 8. As a result, a flow of air passing through theside of the guide roller 3 s and a flow of air passing between the guideroller 3 s and the first guide roller 4 g are formed, and a force in adirection (downward in the present embodiment) away from the pressingposition P1 is applied to the remaining portion of the sheet by theseflows of air. In addition, the distance from the portion of the sheetwhere the force is applied from the air nozzle 4 j 1 to the first guideroller 4 g is smaller than the distance from the first guide roller 4 gto the cutting position by the cutter 4 f.

Here, the first guide roller 4 g is disposed below the pressing roller 4e such that the downstream portion of the first guide roller 4 g is bentupward with respect to the upstream portion of the first guide roller 4g in the conveyance direction in a conveyance path of the sheet. In thisstate, since the urging mechanism 4 j applies a downward force to thesheet, it can more reliably urge the remaining portion of the sheet inthe direction away from the pressing position by utilizing the effect ofgravity.

As indicated by an arrow A2 in FIG. 8, the outlet of the air nozzle 4 j1 can be disposed such that the compressed air blows downward to thedownstream side of the sheet in the conveyance direction from the firstguide roller 4 g in the sheet, specifically, the portion between thefirst guide roller and the cutter 4 f Even in this case, the force inthe direction away from the pressing position P1 is applied to theremaining portion of the sheet.

Hereinafter, the sheet supply operation by the sheet supply device 1will be described. In the following description, it is assumed that theoperation is started from the state in which the sheet of the roll R1supported by the support shaft 3 c is supplied.

As shown in FIG. 1, in the state in which the rotation member 3 b isrotated such that the support shaft 3 d is disposed at the mountingposition, the sheet is conveyed from the roll R1 supported by thesupport shaft 3 c in the direction away from the rotation shaft 3 a.Specifically, the sheet of the roll R1 is guided upward toward the guideroller 3 u adjacent to the support shaft 3 d, the conveyance directionof the sheet is changed downward by the guide roller 3 u, changed upwardby the third guide roller 4 i of the moving unit 4 b, and furthermorechanged downward by the second guide roller 4 h. The sheet guided to thesecond guide roller 4 h is conveyed to the downstream side via aplurality of rollers 2 l provided below the moving unit 4 b in the base2. A roller 2 l shown at the bottom of FIG. 1 in the plurality ofrollers 2 l is driven by a motor (not shown), and one disposed above theroller 2 l is a tension control roller. That is, a tension controlroller 2 l is provided between the moving unit 4 b and a driving roller2 l.

In addition, in the state shown in FIG. 1, the standby side roll (rollR2 in the figure) around which the sheet to be subsequently conveyed iswound is mounted on the support shaft 3 d disposed at the mountingposition.

After the standby side roll is mounted, a worker performs apredetermined operation, and as a result, the rotation member 3 b isrotated counterclockwise, and the support shaft (support shaft 3 d inthe figure) supporting the standby side roll is disposed at the spliceposition shown in FIG. 11 via the posture shown in FIG. 10. In thisstate, the sheet of the supply side roll (roll R1 in the figure) isguided downward from the supply side roll by the guide roller 3 sdisposed below both support shafts 3 c and 3 d, the conveyance directionof the sheet is changed upward by the guide roller 3 s, and the sheet ofthe supply side roll is guided to the guide roller 3 u adjacent to thestandby side roll. The conveyance direction of the sheet of the supplyside roll is changed upward by the guide roller 3 u and the sheet isguided to the moving unit 4 b. In this way, the sheet of the supply sideroll is guided to the moving unit by the guide rollers 3 s and 3 u inthe state in which the standby side roll bypasses to the lower side.

Specifically, the guide roller 3 u is fixed to the rotation member 3 bsuch that the guide roller 3 u is positioned below the pressing roller 4e on a side near the pressing roller 4 e with the support shaft 3 ddisposed at the splice position, and on an outer side of a circulartrajectory C2 (see FIG. 11) drawn by a portion positioned farthest fromthe rotation shaft 3 a on the outer peripheral surface (outer peripheralsurface of the standby side roll having the assumed maximum outerdiameter) of the standby side roll according to the rotation of therotation member 3 b. Preferably, the guide roller 3 u is fixed to therotation member 3 b such that the guide roller 3 u is positioned on theopposite side to the standby side roll based on the tangential line c1to the outer peripheral surface of the standby side roll at the pressingposition P1. The conveying direction of the sheet supplied from thesupply side roll is changed by the guide roller 3 u at the outer side ofthe circular trajectory C2, preferably, on the opposite side to thestandby side roll based on the tangential line c1, and the sheet isguided to a position between the pressing roller 4 e and the standbyside roll.

When the rotation member 3 b is rotated from the above-describedmounting position (FIG. 1) to the splice position (FIG. 11), the movingunit 4 b is disposed at the retracted position shown in FIGS. 1 and 10which is farthest away from the rotation shaft 3 a in the X direction.Note that the retracted position of the moving unit 4 b is set on theouter side of the above-described trajectory C2 (see FIG. 11). At thistime, the support shaft (support shaft 3 d in FIG. 1) supporting thestandby side roll stops, and the adhesion member detector 4 d isdisposed at the retracted position.

As shown in FIG. 11, since the second guide roller 4 h is fixed to themoving unit 4 b on the downstream side of the pressing roller 4 e in theconveyance direction of the sheet, the sheet being conveyed comes intocontact with the peripheral surface of the pressing roller 4 e in thestate in which the standby side roll is disposed at the splice position.As a result, the moving unit 4 b is rotated by the sheet being conveyedin the state of being positioned at the detection standby position P2,and then is less likely to affect the tension and the like of the sheetbeing conveyed as compared to the case where the moving unit 4 b comesinto contact with the sheet during the joining operation.

In addition, when the standby side roll is disposed at the spliceposition, the outer diameter of the standby side roll is detected by theouter diameter detector 4 a while the standby side roll is rotated. Onthe basis of the result of detection, the moving unit 4 b moves from theretracted position to a detectable position (detection standby position)P2 where the adhesion member H of the standby side roll can be detectedby the adhesion member detector 4 d. The detectable position P2 is seton a straight line connecting between the center of the support shaft(support shaft 3 d in FIG. 11) that supports the standby side roll and arotation center of the pressing roller 4 e. When the moving unit 4 bmoves to the detectable position P2, the adhesion member detector 4 d isrotated from the retracted position to the detected position. Thedetectable position P2 can secure the preset accuracy as the accuracy ofthe detection of the adhesion member H by the adhesion member detector 4d, and is set such that the adhesion member detector 4 d at the detectedposition is at the farthest position from the outer peripheral surfaceof the standby side roll. Specifically, in the state where thedetectable position P2 is disposed at the detectable position P2, thedistance from the outer peripheral surface of the standby side roll tothe tip portion of the adhesion member detector 4 d at the detectedposition is, for example, 70 mm.

When the adhesion member detector 4 d moves to the detectable positionP2, as shown in FIG. 12, the position of the adhesion member H in therotation direction of the standby side roll is detected by the adhesionmember detector 4 d while the standby side roll is rotated. On the basisof the result of detection, the standby side roll is rotated such thatthe adhesion member H is positioned within the detection range (withinthe range intersecting the detection axis D1) of the outer diameterdetector 4 a, and in this state, the outer diameter of the portion ofthe adhesion member H on the outer peripheral surface of the standbyside roll is detected by the outer diameter detector 4 a.

Next, as shown in FIG. 13, the adhesion member detector 4 d moves to theretracted position, the support shaft (support shaft 3 d in FIG. 12)supporting the standby side roll is rotated according to the sheetconveyance speed, and the moving unit 4 b is started to move the standbyside roll. As will be described in detail later, during the movement ofthe moving unit 4 b, the position of the unit drive source 4 c 3 iscontrolled in a state in which the pressing roller 4 e is positioned inan area farther away from the standby side roll than the controlswitching position P3 shown in FIG. 13. On the other hand, in the statewhere the pressing roller 4 e is positioned in the area from the controlswitching position P3 to the outer peripheral surface of the standbyside roll, the unit drive source 4 c 3 is torque-controlled. The controlswitching position P3 is set at a position farther away from thepressing position P1 than the position separated by a warped quantity ofthe standby side roll in the radial direction. Specifically, the controlswitching position P3 in the present embodiment is a position closer tothe standby side roll than the detectable position P2, and is a positionwhere the distance from the pressing roller 4 e to the outer peripheralsurface (adhesion member H) of the standby side roll is set to be 5 mm.

The state where the pressing roller 4 e is positioned in an area fartheraway from the standby side roll than the control switching position P3means the state in which the portion (tip portion) closest to thesupport shaft in an outer peripheral portion of the pressing roller 4 epressed against the standby side roll is positioned in the area fartheraway from the standby side roll than the control switching position P3.On the other hand, the state in which the pressing roller 4 e ispositioned in the area from the control switching position P3 to theouter peripheral surface of the standby side roll means the state inwhich the tip portion of the pressing roller 4 e is positioned in thearea from the control switching position P3 to the outer peripheralsurface of the standby side roll.

As shown in FIG. 19, during the execution period of the torque controlwith respect to the unit drive source 4 c 3, the pressing roller 4 e ispressed to the pressing position P1 of the standby side roll via thesheet of the supply side roll. Thereby, the sheet of the standby sideroll is joined to the sheet of the supply side roll via the adhesionmember H.

In this state, the cutter 4 f is rotated from the non-cutting positionindicated by the solid line in FIG. 8 to the cutting position indicatedby the two-dot chain line in FIG. 8. Thereby, the sheet of the supplyside roll is cut, and the conveyance of the sheet of the standby sideroll is started (the standby side roll becomes the supply side roll).When the sheet of the standby side roll is cut, the cutter 4 f isrotated to the non-cutting position.

As shown in FIG. 15, when the sheet of the roll (the roll R1 in FIG. 15)which was the supply side roll is cut, the remaining portion of thesheet falls down from the moving unit 4 b. Here, the base 2 is providedwith a cover 2 m that covers the roller 2 l, which is positioned belowthe moving unit 4 b, from above. The cover 2 m can prevent the remainingportion of the sheet from being caught in the sheet conveyance path.

As shown in FIG. 16, the remaining portion of the sheet is wound by therotation of the support shaft (support shaft 3 c in FIG. 16) supportingthe roll that was the supply side roll.

As shown in FIG. 17, the rotation member 3 b is rotated clockwise, andas a result, the support shaft (support shaft 3 c) supporting the rollthat was the supply roll is disposed at the mounting position. In thisstate, the discharge member 3 v shown in FIG. 6 moves toward the tipside of the support shaft 3 c, and as a result, the roll that was thesupply side roll is discharged, and a new standby side roll is mountedon the support shaft 3 c by a worker.

Hereinafter, the controller 5 for realizing the operation of theabove-described sheet supply device will be described with reference toFIG. 18. FIG. 18 is a block diagram showing an electrical configurationof the controller 5.

The controller 5 controls the joining mechanism 4 such that the sheet ofthe supply side roll is joined to the sheet of the standby side rollwhen the remaining quantity of the sheet of the supply side roll isequal to or less than the preset remaining quantity in the state inwhich the sheet of the supply side roll is supplied.

The controller 5 is connected to the rotation member drive source 2 j,an input operation unit 6, the shaft drive sources 4 k and 4 l, theouter diameter detector 4 a, the unit drive source 4 c 3, the revolutiondrive source 4 q, the adhesion member detector 4 d, the cutter drivesource 4 f 4, the urging force generation source 4 j 2, and thedischarge drive source 2 k. The input operation unit 6 is for inputtinga set value and a command value for the sheet supply device 1.

Specifically, the controller 5 is constituted by a combination of a CPU,a RAM, a ROM, and the like, and includes a control area 5 a thatcontrols the operation of the sheet supply device 1 and a storage area 5b that is connected to the control area 5 a and stores set items and thelike.

The control area 5 a causes information used in the control area 5 a tostore in the storage area 5 b and executes control by the units 5 c to 5m on the basis of the information stored in the storage area 5 b.Specifically, the control area 5 a includes a rotation member controlunit 5 c, an input content determination unit 5 d, a shaft control unit5 e, an outer diameter determination unit 5 f, a unit control unit(motor control unit) 5 g, a revolution control unit 5 h, an adhesionmember position determination unit 5 i, a remaining quantity calculationunit 5 j, a cutter control unit 5 k, an urging force control unit 5 l,and a discharge control unit 5 m.

The input content determination unit 5 d determines the contents inputby the input operation unit 6, and transfers a command related to theinput to the rotation member control unit 5 c, the shaft control unit 5e, and the storage area 5 b. A worker inputs turn on/off of a powersupply of the sheet supply device 1, an indication that the standby sideroll has been mounted on the support shaft, a thickness of the sheet ofthe roll, and a diameter of the sheet of the roll (or the number ofturns), and the like through the input operation unit 6.

The rotation member control unit 5 c executes the rotation of therotation member drive source 2 j and stops the rotation, on the basis ofthe command from the input content determination unit 5 d and thesetting stored in the storage area 5 b.

The shaft control unit 5 e drives the shaft drive sources 4 k and 4 land stops the driving, on the basis of the command from the inputcontent determination unit 5 d and the setting stored in the storagearea 5 b. In addition, the shaft control unit 5 e has a sensor, andtransfers information on the positions and rotation speeds of thesupport shafts 3 c and 3 d in the rotation direction obtained by thesensor to the adhesion member position determination unit 5 i and theremaining quantity calculation unit 5 j.

The adhesion member position determination unit 5 i determines theposition of the adhesion member H in the rotation direction of thestandby side roll on the basis of the result of detection from theadhesion member detector 4 d in the state in which the standby side rollis rotated by the shaft control unit 5 e. Specifically, the position ofthe adhesion member H in the rotation direction of the standby side rollis determined on the basis of the result of detection from the adhesionmember detector 4 d and the shaft control unit 5 e.

The outer diameter determination unit 5 f determines the outer diameterof the standby side roll on the basis of the result of detection fromthe outer diameter detector 4 a, and determines whether the determinedouter diameter is within a preset standard range. In addition, the outerdiameter determination unit 5 f transfers information on the determinedouter diameter of the standby side roll to the corresponding controlunit (for example, the rotation member control unit 5 c, the unitcontrol unit 5 g, and the adhesion member position determination unit 5i).

Here, the position of the adhesion member H in the rotation direction ofthe standby side roll detected by the adhesion member positiondetermination unit 5 i is transferred to the shaft control unit 5 e. Theshaft control unit 5 e rotates the standby side roll on the basis of theposition information from the adhesion member position determinationunit 5 i such that the adhesion member H is positioned within thedetection range of the outer diameter detector 4 a. In this state, theouter diameter determination unit 5 f determines the outer diameter ofthe standby side roll in the portion where the adhesion member H ispositioned, on the basis of the detection value of the outer diameterdetector 4 a.

The unit control unit 5 g controls the unit drive source 4 c 3 on thebasis of the outer diameter of the standby side roll determined by theouter diameter determination unit 5 f such that the sheet of the supplyside roll is pressed against the adhesion member H of the standby sideroll. Specifically, the unit control unit 5 g determines the detectableposition P2 (see FIG. 11) of the adhesion member detector 4 d where theadhesion member detector 4 d can avoid contacting with the outerperipheral surface of the standby side roll and where the adhesionmember detector 4 d can detect the adhesion member H on the basis of theresult of detection from the outer diameter detector 4 a. Further, theunit control unit 5 g controls the driving of the unit drive source 4 c3 such that the adhesion member detector 4 d moves to the detectableposition when the detectable position P2 is closer to the support shaftdisposed at the splice position than the retracted position (see FIG.10).

Here, the outer diameter determination unit 5 f determines the outerdiameters of the standby side rolls at a plurality of locations in therotation direction of the standby side roll on the basis of the resultof detection from the outer diameter detector 4 a in the state in whichthe standby side roll is rotated by the shaft drive sources 4 k and 4 l,and determines an average outer diameter of the standby side roll on thebasis of these outer diameters. Then, the unit control unit 5 gdetermines the detectable position on the basis of the average outerdiameter.

Further, the unit control unit 5 g controls the position of the unitdrive source (servomotor) 4 c 3 in the state in which the pressingroller 4 e is positioned in the area farther away from the standby sideroll than the control switching position P3 (see FIG. 13) away from theouter peripheral surface of the standby side roll by a predetermineddistance while the standby side roll is rotated by the shaft controlunit 5 e. On the other hand, the unit control unit 5 g torque-controlsthe unit drive source 4 c 3 in the state in which the pressing roller 4e is positioned in the area from the control switching position P3 tothe outer peripheral surface of the standby side roll, thereby pressingthe pressing roller 4 e against the outer peripheral surface of thestandby side roll via the sheet of the supply side roll.

Here, the position control is control to move the pressing roller to atarget position at a predetermined timing by performing feedback controlusing a deviation between the current position of the pressing rollerdetermined using a sensor having a servomotor and a predetermined targetposition. In addition, the torque control is to control a current valuesupplied to the servomotor such that a torque of the servomotordetermined by the current value supplied to the servomotor becomes apredetermined torque.

Further, the unit control unit 5 g switches the control of the unitdrive source 4 c 3 from the position control to the torque control whilemaintaining the driving of the unit drive source 4 c 3 when the pressingroller 4 e approaches the standby side roll beyond the control switchingposition P3 from the area farther away from the standby side roll thanthe control switching position P3. Here, the control switching positionP3 is set at a position (5 mm in the present embodiment) away from thestandby side roll such that even if the outer peripheral surface of thestandby side roll is warped, the pressing roller 4 e does not come intocontact with the warped outer peripheral surface of the standby sideroll in the state in which the position of the pressing roller 4 e iscontrolled.

Here, the adhesion member position determination unit 5 i determinespressing timing when the adhesion member H arrives at the pressingposition P1 of the standby side roll in the rotation direction of thestandby side roll on the basis of the result of detection from the outerdiameter detector 4 a and the adhesion member detector 4 d, and therotation speed of the support shaft supporting the standby side rollobtained from the shaft control unit 5 e. Here, the shaft control unit 5e controls the driving of the shaft drive sources 4 k and 4 l of thesupport shaft that supports the standby side roll such that the speed ofthe outer peripheral surface of the standby side roll matches theconveyance speed of the sheet of the supply side roll. Further, the unitcontrol unit 5 g specifies the timing for starting the movement of thepressing roller 4 e at which the pressing roller 4 e is pressed to thepressing position at the pressing timing, on the basis of theinformation on the position of the pressing roller 4 e obtained from theunit drive source 4 c 3 and the pressing timing determined by theadhesion member position determination unit 5 i. Specifically,immediately before the joining operation of the sheets, the moving unit4 b is disposed at a splice preparation position (not shown) between thedetectable position P2 shown in FIG. 12 and the control switchingposition P3 shown in FIG. 13, the position control and the torquecontrol of the unit drive source 4 c 3 from the splice preparationposition are executed, thereby the pressing roller 4 e is pressed to thepressing position P1 as shown in FIG. 14. Therefore, the unit controlunit 5 g determines the timing for starting the movement of the pressingroller 4 e on the basis of the movement time of the pressing roller 4 efrom the splice preparation position to the pressing position P1 and thepressing timing. In addition, the unit control unit 5 g starts movingthe pressing roller 4 e (driving the unit drive source 4 c 3) when thetiming arrives. The pressing timing includes not only the timing whenthe adhesion member H arrives at the pressing position P1, but also thetiming when the sheet positioned slightly upstream from the adhesionmember H in the rotation direction of the standby side roll arrives atthe pressing position P1. That is, the timing for starting the movementof the pressing roller is set for the purpose of joining the sheet ofthe supply side roll to the sheet of the standby side roll at the sametime as or immediately after the pressing by the pressing roller 4 e.

The shaft control unit 5 e executes the control to adjust the sheetfeeding quantity from the supply side roll according to the change inthe tension of the sheet due to the change in a path length of the sheeton the supply roll when the rotation member 3 b is rotated between themounting position (see FIG. 1) and the splice position (see FIG. 11).Specifically, the shaft control unit 5 e reduces the feeding quantitywhen the path length of the sheet is shortened, and increases thefeeding quantity when the path length of the sheet extends. The pathlength is changed according to the following three factors. The firstfactor is a rotation angle of the rotation member 3 b, the second factoris an outer diameter dimension of the supply side roll, and the thirdfactor is the position of the moving unit 4 b. The characteristics ofthe feeding quantity for these three factors are determined in advance,a map showing these characteristics is stored in the storage area 5 b,and the feeding quantity is determined by using the map and the detectedvalues of the three factors. During the rotation operation of therotation member 3 b, the shaft control unit 5 e can use only the mapsrelated to the first factor and the second factor. Further, while themoving unit 4 b is moving, the shaft control unit 5 e can use the maprelated to the third factor until the pressing roller 4 e is pressedagainst the standby side roll. While the moving unit 4 b is moving, theshaft control unit 5 e can use the map related to the second factor(outer diameter dimension of a new supply roll) and the third factorafter the pressing roller 4 e is pressed against the standby side roll.Note that in the relationship with the disposition of the guide rollers3 r to 3 u (see FIG. 1) in the support mechanism 3 of the presentembodiment, the change in the path length is the largest within thepredetermined angle range based on the state in which the rotationmember 3 b is rotated horizontally (the state in which one support shaftis disposed at the splice position). Therefore, the speed of the shaftcontrol unit 5 e is lower when the rotation member 3 b is rotated withinthe above angle range than when the rotation member 3 b is rotatedwithin another angle range.

The remaining quantity calculation unit 5 j calculates the remainingquantity of the sheet of the roll by using a thickness t of the sheet onthe roll stored in the storage area 5 b, a final diameter Df of the rollstored in the storage area 5 b when the supply of the sheet iscompleted, a supply length L of the sheet supplied from the roll perrotation at the time of calculation, and a rotation speed v of thesupport shaft obtained from the shaft control unit 5 e. The finaldiameter Df of the roll is a diameter of a core for a roll having acore, or the diameter of the support shaft for a roll without the core.In addition, the supply length L of the sheet is calculated, forexample, from the rotation speed (peripheral speed) of the motor-drivenroller 2 l and the rotation speed v of the support shaft shown at thebottom of FIG. 1

Specifically, the remaining quantity calculation unit 5 j calculates acurrent diameter Dp of the roll by dividing the supply length L of thesheet per rotation by π. Further, the remaining quantity calculationunit 5 j may calculate the diameter Dp in consideration of a change in aconveyance path length of the sheet by the tension control roller 2 lshown in FIG. 1. Then, the remaining quantity of the sheet is calculatedbased on the following equation (1).

[(Dp+Df)/2×π]×[(Dp−Df)/2t]  (1)

Here, the first [ ] is for calculating an average diameter of one roundof the sheet wound around a plurality of times, and the last [ ] is thenumber of times of winding. According to Equation (1), the remainingquantity of the sheet can be calculated (estimated) by multiplying thenumber of windings by a circumference of the average diameter. Note thatthe thickness t of the sheet may be calculated by dividing a decreasevalue per rotation of the diameter Dp of the roll that is decreasing foreach rotation of the roll by two. In addition, the remaining quantitycalculation unit 5 j can also calculate (estimate) the remainingquantity of the sheet using a mass of the standby side roll.

As described later, the controller 5 starts an operation for joining thesheet of the standby side roll when the remaining quantity of the sheetof the supply side roll calculated by the remaining quantity calculationunit 5 j becomes equal to or less than the preset remaining quantity ofthe sheet. Here, the preset remaining quantity of the sheet is aremaining quantity of sheet of the supply roll when the preparationoperation for joining the sheet of the standby side roll to the sheet ofthe supply roll is started, and is set by adding the following threetimes required for the preparation operation to the remaining quantityof the sheet of the supply side roll remaining after the joiningoperation is completed. A first time is a time from the start of therotation of the standby side roll until the rotation speed arrives atthe sheet conveyance speed. A second time is a time from the start ofthe advance of the moving unit 4 b for pressing the pressing roller 4 eto the pressing position P1 until the pressing roller 4 e arrives at thepressing position P1. A third time is a time until the rotation of theroll which was the supply side roll stops after the sheets are joined.The remaining quantity of the sheet is set using a value obtained byadding a value obtained by multiplying the conveyance speed of the sheetby the first time and the second time, and a value obtained bymultiplying the circumference of the roll by the number of rotations ofthe roll which was the supply roll during the third time. The standbyside roll may be rotated in advance at a predetermined speed before thepreparation operation, and in this case, the remaining quantity of thesheet can be set without considering the first time.

The cutter control unit 5 k outputs an operation command to the cutterdrive source 4 f 4, thereby driving the cutting blade 4 f 2 between anon-cutting position indicated by a solid line and a cutting positionindicated by a two-dot chain line in FIG. 8. In addition, the cuttercontrol unit 5 k sets the driving timing for driving the cutting blade 4f 2 to the cutting position based on the above-described pressing timingdetermined by the unit control unit 5 g. For example, the cutter controlunit 5 k drives the cutting blade 4 f 2 to the cutting positionimmediately after the pressing timing (for example, after 60milliseconds), and holds the cutting blade 4 f 2 at the cutting positionfor a predetermined period (for example, 60 milliseconds).

The urging force control unit 5 l outputs the operation command to theurging force generation source 4 j 2, thereby switching the urgingmechanism 4 j to a supply state in which compressed air blows from theair nozzle 4 j 1 according to the cutting timing of the sheet by thecutter 4 f Specifically, the urging force control unit 5 l sets theurging mechanism 4 j in the supply state during a predetermined periodincluding the cutting timing of the sheet. Further, the urging forcecontrol unit 5 l may control the urging mechanism 4 j such that theurging mechanism 4 j is in the supply state during a period from beforethe predetermined time of the cutting timing to after the lapse of thepredetermined time. In the present embodiment, the urging force controlunit 5 l switches the urging mechanism 4 j from the stop state to thesupply state simultaneously with the driving timing of the cutter blade4 f 2 by the cutter control unit 5 k, and maintains the supply state forthe predetermined period (for example, 100 seconds). The urging forcecontrol unit 5 l sets the switching timing of the urging mechanism 4 jbased on the above-described pressing timing determined by the unitcontrol unit 5 g.

The discharge control unit 5 m outputs an operation command to thedischarge drive source 2 k to control the discharge mechanism between anon-discharge position indicated by a solid line and a dischargeposition indicated by a two-dot chain line in FIG. 6.

The revolution control unit 5 h controls the revolution drive source 4 qsuch that the adhesion member detector 4 d moves between the detectedposition (see FIG. 12) and the retracted position (see FIG. 13).

Hereinafter, the processing executed by the controller 5 will bedescribed with reference to FIGS. 18 to 22. In the followingdescription, a case in which the current sheet is supplied from the rollR1 supported by the support shaft 3 c and a new roll R2 is mounted onthe support shaft 3 d, that is, a case in which the roll R1 is thesupply side roll and the roll R2 is the standby side roll will bedescribed. In addition, it is assumed that the support shaft 3 c isrotatably driven at the stage before the execution of the processingshown in FIG. 19, and thus the sheet of the supply side roll R1 issupplied.

Referring to FIG. 19, when the input operation unit 6 is operated by aworker to allow the sheet supply device 1 to perform the joiningoperation of the sheet, the rotation member 3 b is rotated such that thesupport shaft 3 d is disposed at the mounting position shown in FIG. 1(step S1). A worker mounts a new standby side roll R2 on the supportshaft 3 d rotated to the mounting position in this way.

After the new standby side roll R2 is mounted, when the input operationunit 6 for inputting the completion of the mounting by the worker isoperated (YES in step S2), the rotation member 3 b is rotated such thatthe support shaft 3 d is disposed at the splice position shown in FIG.11 (step S3).

In this state, the standby side roll R2 is rotated (step S4). Further,the outer diameter detector 4 a starts detecting the outer diameter ofthe standby side roll R2, the rotation of the standby side roll R2 isstopped at the timing when the outer diameter of the standby side rollR2 is detected during one rotation of the standby side roll R2, and theaverage value of the outer diameter of the standby side roll R2 iscalculated on the basis of the detection value of the outer diameter(step S5).

It is determined whether or not the average value of the outer diameterof the standby side roll R2 calculated in this way is within apredetermined standard range (step S6). Here, if it is determined thatthe average value is out of the standard range (NO in step S6), therotation member 3 b is rotated such that the support shaft 3 d isdisposed at the mounting position shown in FIG. 1 (step S7), and theprocess returns to the above-described step S2. That is, when the outerdiameter of the standby side roll R2 is out of the standard range, thestandby side roll R2 is not used to be replaced with (mounted on)another standby side roll R2 after the support shaft 3 d is disposed atthe mounting position.

On the other hand, if it is determined that the average value of theouter diameter of the standby side roll R2 is within the standard range(YES in step S6), the moving unit 4 b moves to a position for detectionby the outer diameter detector 4 a and the adhesion member detector 4 d(step S8).

Specifically, in step S8, the detectable position is calculated on thebasis of the average value of the outer diameter of the standby sideroll R2 calculated in step S5. Further, when the position of the movingunit 4 b corresponding to the detectable position is closer to thestandby side roll R2 than the retracted position shown in FIG. 1, themoving unit 4 b moves to a position corresponding to the detectableposition P2 (FIG. 12). On the other hand, when the position of themoving unit 4 b corresponding to the detectable position is theretracted position or is farther from the standby side roll R2 than theretracted position, the moving unit 4 b waits at the retracted position.

Next, the adhesion member detector 4 d is rotated from the retractedposition shown in FIG. 10 to the detected position shown in FIGS. 11 and12 (step S9), and the rotation of the standby side roll R2 is started(step S10), and in this state, the position of the adhesion member H inthe rotation direction of the standby side roll R2 is detected by theadhesion member detector 4 d (step S11).

The rotation of the standby side roll R2 stops such that the adhesionmember H is disposed within the detection range of the outer diameterdetector 4 a as indicated by a two-dot chain line in FIG. 12 (such thatthe adhesion member H is positioned within the range that intersects thedetection axis D1) on the basis of the detected position of the adhesionmember H in the rotation direction (step S12).

In this state, the outer diameter of the adhesion member H in thestandby side roll R2 is detected by the outer diameter detector 4 a(step S13).

Next, as shown in FIG. 13, the adhesion member detector 4 d moves to theretracted position (step S14), and the moving unit 4 b advances to thesplice preparation position (step S15). Here, the splice preparationposition is a position between the detectable position P2 shown in FIG.12 and the control switching position P3 shown in FIG. 13, and is aposition preset as a position where the pressing roller 4 e does notcome into contact with the standby side roll R2 even if the outerdiameter of the standby side roll R2 varies in the rotation direction.For example, the splice preparation position is the position of themoving unit 4 b where the distance from the pressing roller 4 e to theouter diameter of the standby side roll R2 is 50 mm.

Next, the remaining quantity of the supply side roll R1 is calculated(step S16), and it is determined whether the remaining quantity is equalto or less than the preset remaining quantity (predetermined quantity)(step S17).

If it is determined in step S17 that the remaining quantity is not equalto or less than the predetermined quantity, the remaining quantity ofthe supply side roll R1 is repeatedly calculated based on the rotationspeed v of the support shaft 3 c and the conveyance speed of the sheet(step S16), and it is determined whether the remaining quantity is equalto or less than the predetermined quantity (step S17).

Here, if it is determined that the remaining quantity is equal to orless than the predetermined quantity, the rotation of the standby sideroll R2 is started so as to have the same speed as the conveyance speedof the sheet of the supply side roll R1 (step S18).

In step S19, the driving timings of the moving unit 4 b, the cutter 4 f,and the urging mechanism 4 j are set. Specifically, the unit controlunit 5 g sets the driving timing of the moving unit for pressing thepressing roller 4 e to the pressing position P1 via the adhesion memberH. The cutter control unit 5 k sets the driving timing for driving thecutting blade 4 f 2 to the cutting position according to the pressingtiming of the pressing roller 4 e. Further, the urging force controlunit 5 l sets the driving timing of the urging mechanism 4 j that blowsout the compressed air according to the sheet cutting timing.

Next, it is determined whether or not the driving timing of the movingunit 4 b has come (step S20), and if it is determined that the drivingtiming has arrived, the moving unit 4 b advances from a splice standbyposition (not shown) by position control (step S21).

When the moving unit 4 b starts advancing in step S21, it is determinedwhether the moving unit 4 b has arrived at the control switchingposition P3 shown in FIG. 13 (step S22).

Here, if it is determined that the moving unit 4 b has not arrived atthe control switching position P3, the moving unit 4 b continues toadvance by the position control, while if it is determined that themoving unit 4 b has arrived at the control switching position P3, thecontrol for advance of the moving unit 4 b is switched to the torquecontrol (step S23).

In parallel with steps S20 to S23, it is determined whether or not thedriving time of the cutter 4 f has come (step S24).

Here, if it is determined that the driving time of the cutter 4 f hasarrived, the cutter 4 f is driven to the cutting position (step S25).Thereby, the sheet of the supply side roll R1 is cut, and the supply ofthe sheet of the standby side roll R2 is started.

In parallel with steps S20 to S23 and steps S24 to S25, it is determinedwhether or not the driving time of the urging mechanism 4 j has come(step S26).

If it is determined that the driving time of the urging mechanism 4 jhas arrived, the urging mechanism 4 j applies the urging force (stepS27). Thereby, after the sheet of the supply side roll R1 is cut by thecutter 4 f, the remaining portion of the sheet is urged in a direction(downward) away from the pressing roller 4 e to be able to prevent thesheet from being caught in a supply path of the sheet.

After executing the processes related to steps S20 to S23, steps S24 toS25, and steps S26 to S27, it is determined whether or not the movementof the moving unit 4 b to the pressing position, the driving of thecutter 4 f to the cutting position, and the application of the urgingforce from the urging mechanism 4 j are completed, in other wordswhether or not the joining operation is completed (step S28).

If it is determined in step S28 that the joining operation is notcompleted, the process waits for the completion of all the processes insteps S20 to S27, while if it is determined that the joining operationis completed, the role setting is changed (step S29). Specifically, instep S29, the roll R1 is set as the next standby side roll, and the rollR2 is set as the next supply side roll.

Next, the moving unit 4 b retracts by the torque control (step S30), andwhen the moving unit 4 b arrives at the control switching position P3(see FIG. 13) (YES in step S31), the moving unit 4 b is temporarilystopped (step S32).

Then, the moving unit 4 b retracts by the position control (step S33),and when the moving unit 4 b arrives at the retracted position (seeFIG. 1) (YES in step S34), the moving unit 4 b is stopped (step S35).

Further, in parallel with the steps S30 to S35, the cutter 4 f is drivenat the non-cutting position (step S36), the rotation of the supportshaft 3 c is stopped (step S37), and the application of the urging forceis stopped (step S38).

Then, it is determined whether or not all the processes in steps S30 toS38 are completed (step S39). Here, if it is determined that some of theprocesses in steps S30 to S38 are not completed, the process waits untilall the processes in steps S30 to S38 are completed.

On the other hand, if it is determined in step S39 that all theprocesses in steps S30 to S38 are completed, the support shaft 3 c isreversed by a predetermined angle (step S40). Thereby, the remainingportion of the sheet cut by the cutter 4 f is wound around the supportshaft 3 c from the state shown in FIG. 15, as shown in FIG. 16.

Next, the rotation member 3 b in the state of FIG. 16 is rotatedclockwise in FIG. 16 about the rotation shaft 3 a, so the support shaft3 d is disposed at the mounting position (see FIG. 1) (step S41).

In this state, as shown in FIG. 6, the discharge mechanism is drivenfrom the non-discharge position indicated by a solid line to thedischarge position indicated by a two-dot chain line (step S42).Thereby, the roll R1 is discharged from the support shaft 3 c disposedat the mounting position, and then, a worker is allowed to attach a newroll. Then, the process returns to step S2.

As described above, the position where the sheet of the supply side rollR1 is joined to the outer peripheral surface of the standby side rollR2, that is, the outer diameter of the standby side roll R2 at theposition where the adhesion member H is positioned is detected, and thesheet of the supply side roll R1 can be pressed against the adhesionmember H of the standby side roll R2 on the basis of the outer diameter.

Therefore, even if the standby side roll R2 has different outerdiameters at each position in the rotation direction (even if thestandby side roll R2 is warped), the pressing quantity (distance) of thesheet of the supply side roll R1 can be set to be a pressing quantitysuitable for the position of the adhesion member H in the radialdirection.

Therefore, even if the standby side roll R2 is warped, the sheet of thesupply side roll R1 can be reliably joined to the sheet of the standbyside roll R2.

According to the embodiment, the following effects can be obtained.

When the standby side roll R2 having the assumed maximum outer diameteris held on the support shaft 3 d, the contact with the standby side rollR2 can be avoided by disposing the adhesion member detector 4 d (movingunit 4 b) at the retracted position. In addition, when the standby sideroll R2 having a smaller outer diameter than the standby side roll R2having the maximum outer diameter is held on the support shaft 3 d, theadhesion member detector 4 d is disposed at a position closer to thesupport shaft 3 d than the retracted position (detectable position P2:see FIG. 12). As a result, comparing with the case where the adhesionmember detector 4 d is fixed to the retracted position, even if thedetection performance of the adhesion member detector 4 d decreases, theposition of the adhesion member H in the rotation direction of thestandby side roll R2 can be accurately detected. Thereby, cost can bereduced.

The detectable position P2 is determined on the basis of the averageouter diameter of the standby side roll R2. Therefore, it is possible tomore reliably determine the detectable position P2 that can avoid thecontact of the outer diameter detector 4 d with the standby side roll R2as compared with the case where the detectable position P2 is determinedbased only on the outer diameter of the standby side roll R2 at theposition of the adhesion member H.

The moving unit 4 b can also be used as the support member of thepressing roller 4 e, and the unit drive source 4 c 3 capable of movingthe adhesion member detector 4 d can also be used as a drive source formoving the pressing roller 4 e with respect to the standby side roll R2.Therefore, the cost of the sheet supply device 1 can be reduced ascompared with the case where the support member and the drive source areseparately provided.

Since it is possible to always keep the detection axis D2 (see FIG. 12)perpendicular to the outer peripheral surface of the standby side rollR2 between the retracted position and the advance position (see FIG. 14:proximity position) closer to the standby side roll R2 than theretracted position, the accuracy of detection can be kept constantregardless of the change in the outer diameter of the standby side rollR2.

In addition, by setting the revolution member 4 n at the detectedposition, the adhesion member detector 4 d can be disposed between thesupport shaft 3 d and the pressing roller 4 e to detect the outerdiameter of the standby side roll R2. Further, by revolving therevolution member 4 n to the retracted position, the pressing roller 4 e(the sheet of the supply side roll R1) can be pressed against thestandby side roll R2.

In addition, in the above embodiment, although the structure which blowsout the compressed air is employed as the urging mechanism 4 j, theurging mechanism 4 j is not limited to the structure of the aboveembodiment. For example, as shown in FIG. 23, the urging mechanism 7that presses the sheet mechanically may be employed as the urgingmechanism 4 j.

Specifically, the urging mechanism 7 includes an air cylinder 7 aattached to the moving unit 4 b and a pressing plate 7 b for pressing asheet.

The air cylinder 7 a has a cylinder main body 7 c fixed to the movingunit 4 b, and a rod 7 d displaceable with respect to the cylinder mainbody 7 c, and the rod 7 d can be expanded and contracted with respect tothe cylinder main body 7 c by supplying the compressed air from theurging force generation source (not shown).

The pressing plate 7 b is fixed to the rod 7 d so as to follow theexpansion and contraction of the rod 7 d.

As described above, the urging mechanism 7 controls the supply andexhaust of the compressed air from the urging force generation source(not shown), and as a result, is configured to be switchable between asupply state (state indicated by a two-dot chain line in FIG. 23) inwhich a force is applied to the sheet in a direction away from thepressing position P1 (see FIG. 8) and a stop state in which theapplication of the force is stopped.

Hereinafter, a sheet supply method using the above-described sheetsupply device 1 will be described. Hereinafter, the case where the rollR1 in FIG. 1 is the supply side roll and the roll R2 is the standby sideroll will be described.

The sheet supply method includes a mounting step, a supply step, asplice preparation step, and a joining step.

In the mounting step, the standby side roll R2 is mounted on the supportshaft 3 d mounted at the mounting position shown in FIG. 1.

In the supply step, prior to the mounting step, the sheet of the supplyside roll R1 supported at the center position by the support shaft 3 cis supplied by the driving of the shaft drive source 4 l.

In the splice preparation step, when the remaining quantity of the sheetof the supply side roll R1 is equal to or less than the preset remainingquantity, the rotation member 3 b is rotated such that the support shaft3 d is disposed at the splice position as shown in FIG. 11.

In the joining step, in a state after the splice preparation step isperformed, as shown in FIG. 14, the pressing roller 4 e moves such thatthe center of the pressing roller 4 e moves on the straight line passingthrough the center of the rotation shaft 3 a and the center of thesupport shaft 3 d disposed at the splice position by the joiningmechanism 4 (steps S20 to S23 in FIG. 21). As a result, the sheet of thesupply side roll R1 is pressed against the outer peripheral surface ofthe standby side roll R2, and the sheet of the standby side roll R2 isjoined to the sheet of the supply side roll R1. Then, in the joiningstep, as indicated by a two-dot chain line in FIG. 8, after the sheet ofthe supply side roll R1 is joined to the sheet of the standby side rollR2, the sheet of the supply side roll R1 is cut by the cutter 4 f.

Further, in the joining process, the position control of the unit drivesource 4 c 3 is executed in the state in which the pressing roller 4 eis positioned in the area farther away from the standby side roll R2than the control switching position P3 (see FIG. 13) away from the outerperipheral surface of the standby side roll R2 by a predetermineddistance while the standby side roll R2 is rotated by the shaft drivesource (second shaft drive source) 4 k. On the other hand, in thejoining step, the torque control of the unit drive source 4 c 3 isexecuted in the state in which the pressing roller 4 e is positioned inthe area from the control switching position P3 to the outer peripheralsurface of the standby side roll R2, thereby pressing the pressingroller 4 e against the outer peripheral surface of the standby side rollR2 via the sheet of the supply side roll R1.

Thus, in the joining step, the moving unit 4 b moves in a directionapproaching the standby side roll R2. As a result, as shown in FIG. 8,the second guide roller 4 h fixed to the moving unit 4 b is disposed onthe opposite side to the standby side roll R2 based on the tangentialline C1 with respect to the outer peripheral surface of the standby sideroll R2 at the pressing position P1. Thereby, the sheet is guided suchthat the sheet is guided from the pressing roller 4 e in a directionaway from the standby side roll R2.

Further, in the joining step, as shown in FIG. 8, by moving the movingunit 4 b in the direction approaching the standby side roll R2, thepressing roller 4 e is pressed against the pressing position, and thesheet drawn from the supply side roll R1 on the upstream side of thepressing position P1 in the conveyance direction of the sheet is guidedto the pressing position P1 by the first guide roller 4 g. Further, theforce in the direction away from the pressing position P1 is applied tothe portion of the sheet of the supply side roll R1 on the upstream sidein the conveyance direction with respect to the cutting position by thecutter 4 f according to the sheet cutting timing by the cutter 4 f

Although the example in which the supply step is performed prior to themounting step has been described, for example, when the sheet supplydevice 1 is started, the mounting step may be performed before thesupply step.

Note that the present invention is not limited to the above embodiment,and for example, the following aspects can be adopted.

In the above embodiment, although the double-sided tape is illustratedas the adhesion member H, the adhesion member H is not limited to thedouble-sided tape, and is provided on the outer peripheral surface ofthe standby side roll, and may allow the adhesion from the outside ofthe sheet of the supply side roll while fastening an end of the sheet onthe outer peripheral surface of the standby side roll. For example, theadhesion member H does not have a base material such as a tape, but maybe an adhesive. Further, a tape having a delamination structure in whicha plurality of layers are laminated so as to be peelable and which hasan adhesive material on both front and back surfaces thereof can also beadopted. Specifically, the tape having the delamination structure isstuck on the outer peripheral surface of the standby side roll, and theend portion of the sheet is bonded to the outer surface of the tape sothat a part of the outer surface of the tape is exposed. In this state,by pressing the sheet of the supply side roll against the exposedportion of the tape, an outermost layer of the tape having thedelamination structure is peeled from an inner layer thereof, and thusthe sheets can be joined.

In the above embodiment, although the configuration in which the supportshafts 3 c and 3 d are provided at every 180° about the rotation shaft 3a with respect to the rotation member 3 b has been described, the numberof support shafts to be attached to the rotation member 3 b is notlimited to two, but may be in plural. For example, it is also possibleto apply the rotation member 3 b provided with three support shaftsevery 120° about the rotation shaft 3 a.

Although the configuration in which the moving unit 4 b moves in ahorizontal direction has been described, the moving direction of themoving unit 4 b is not limited to the horizontal direction. For example,the moving unit 4 b can be configured to move in a vertical direction orin a direction inclined with respect to the horizontal direction and thevertical direction. However, it is preferable to set the movement pathof the moving unit 4 b such that a space for the remaining portion ofthe sheet cut by the cutter 4 f to fall can be formed below the movingunit 4 b.

Although the support shafts 3 c and 3 d supported (extending in the Ydirection from the rotation member 3 b) in a cantilever manner withrespect to the rotation member 3 b have been described, both ends of thesupport shafts 3 c and 3 d may be supported. However, as in the aboveembodiment, since one end of each of the support shafts 3 c and 3 d is afree end, the rolls R1 and R2 can be easily mounted from the free end.

Although the urging mechanism 4 j (FIG. 8) for blowing the compressedair and the urging mechanism 7 (FIG. 23) for pressing the pressing plate7 b have been described, the urging mechanism is not limited to theseconfigurations. For example, the drive source for rotating the guideroller (for example, the first guide roller 4 g in FIG. 8) in adirection opposite to the conveyance direction of the sheet is appliedas the urging mechanism, the guide roller being provided on the upstreamside of the cutter 4 f in the conveyance path of the sheet.

The configuration in which the cutter 4 f is driven to the cuttingposition immediately after the pressing timing of the pressing roller 4e to the pressing position P1 has been described, but the timing ofdriving the cutter 4 f to the cutting position is not limited thereto.For example, the cutter 4 f can be driven to the cutting positionsimultaneously with the pressing timing. Thereby, after the joiningoperation, the length of the portion following the sheet of the standbyside roll in the sheet of the supply side roll can be shortened.

Although the configuration in which the average value of the outerdiameter is calculated based on the result of detection from the outerdiameter detector 4 a while the standby side roll is rotated once hasbeen described, the method of calculating the outer diameter of thestandby side roll is not limited thereto. For example, in the state inwhich the rotation of the standby side roll is stopped, the outerdiameter of the standby side roll at one location in a circumferentialdirection may be calculated based on the result of detection from theouter diameter detector 4 a. Further, when the average value of theouter diameter is calculated, the rotation range of the standby sideroll is not one rotation but may be shorter (for example, shortened to ahalf rotation) than the one rotation.

Although the configuration in which the pressing roller 4 e and theadhesion member detector 4 d are each attached to the common moving unit4 b has been described, the pressing roller 4 e and the adhesion memberdetector 4 d may be attached to different configurations that can becontact with and separated from the standby side roll.

Although the example in which the detection axis D2 (see FIG. 12) of theadhesion member detector 4 d is disposed perpendicular (perpendicular tothe support shafts 3 c and 3 d) to the outer peripheral surface of thestandby side roll has been described, the detection axis D2 may not bedisposed perpendicular to the standby side roll.

Furthermore, the example in which the adhesion member detector 4 d isrotatable between the detected position (see FIG. 12) and the retractedposition (see FIG. 13) by the revolution member 4 n has been described,but the attachment method of the adhesion member is not limited thereto.For example, the adhesion member may be fixed at a position where thedetection axis D2 intersects the outer peripheral surface of the standbyside roll under the premise that the adhesion member is disposed at aposition deviating from the movement path of the pressing roller 4 e.

In the above embodiment, when the moving unit 4 b moves to the controlswitching position P3, the switching from the position control to thetorque control is performed without stopping the moving unit 4 b (stepsS21 to S23 in FIG. 21), but the control of the moving unit 4 b is notlimited thereto. For example, it is also possible to stop the movingunit 4 b at the control switching position P3 and then perform theswitching from the position control to the torque control.

In the above embodiment, the switching timing from the position controlto the torque control is calculated while the moving unit 4 b is waitingat the splice preparation position (not shown) (step S15 in FIG. 20 andstep S19 in FIG. 21), but the calculation time of the switching timingis not limited thereto. For example, under the premise that the pressingroller 4 e is temporarily stopped when the pressing roller 4 e arrivesat the control switching position P3, the start timing of the torquecontrol may be determined when the pressing roller 4 e arrives at thecontrol switching position P3.

In the above embodiment, the configuration in which the sheet of thesupply side roll (the roll R1 in FIG. 11) is guided between the standbyside roll and the pressing roller 4 e through below the standby sideroll (the roll R2 in FIG. 11) has been described, but the path forguiding the sheet to the pressing position P1 is not limited thereto.For example, the configuration in which the sheet of the supply sideroll is guided between the standby side roll and the pressing roller 4 ethough over the standby side roll may be employed.

In the embodiment, as shown in FIG. 8, in the moving unit 4 b, the firstguide roller 4 g is provided on the upstream side of the pressingposition P1 in the conveyance direction of the sheet, but the secondguide roller 4 h is provided on the downstream side of the pressingposition P1. The angle θ1 formed by the sheet from the first guideroller 4 g to the pressing position P1 and the tangential line C1 issmaller than the angle θ2 formed by the sheet from the pressing positionP1 to the second guide roller 4 h and the tangential line C1. However,the angle θ1 may be equal to or larger than the angle θ2.

The point where the urging mechanism 4 j is switched from the stoppedstate to the switched state at the same time as the driving timing ofthe cutting blade 4 f 2 (steps S24 to S27) has been described. However,the switching of the urging mechanism 4 j from the stop state to thesupply state according to the driving timing of the cutting blade 4 f 2includes that the urging mechanism 4 j is in the supply state during apredetermined period including the driving timing of the cutting blade 4f 2, and after the driving of the cutting blade 4 f 2, the urgingmechanism 4 j is in the supply state during a predetermined period fromtiming before the remaining portion of the sheet of the supply side rollfollows the sheet of the standby side roll and is caught in theconveyance path.

Although the configuration in which the force from the urging mechanism4 j is applied to the portion of the sheet opposite to the cutter 4 fbased on the first guide roller 4 g on the sheet has been described, theposition where the force from the urging mechanism 4 j is applied may bea portion on the upstream side in the conveyance direction with respectto the cutting position of the sheet by the cutter 4 f For example, asshown in FIG. 23, the force from the urging mechanisms 4 j and 7 can beapplied to a position on the upstream side in the conveyance directionwith respect to the cutting position by the cutter 4 f and on thedownstream side of the first guide roller 4 g.

The configuration in which the distance from the portion of the sheet towhich the force from the urging mechanism 4 j is applied to the firstguide roller 4 g is set smaller than the distance from the first guideroller 4 g to the cutting position by the cutter 4 f has been described,but the distance is not particularly limited.

Although the urging mechanism 4 j for applying a downward force to thesheet has been described, the direction of the force from the urgingmechanism may be a direction away from the pressing position P1.

In the above embodiment, the distance from the portion of the sheet towhich the force is applied by the urging mechanism 4 j to the firstguide roller 4 g is smaller than the distance from the first guideroller 4 g to the cutting position by the cutter 4 f. However, theportion of the sheet to which the force from the urging mechanism 4 j isapplied may be positioned on the upstream side away from the first guideroller 4 g. For example, the force from the urging mechanism 4 j may beapplied to a portion of a sheet on a further upstream side with respectto the guide roll 3 s.

In order to obtain the result of detection from the outer diameterdetector 4 a in the state in which the position of the adhesion member Hdetermined by the adhesion member position determination unit 5 i ispositioned within the detection range of the outer diameter detector 4a, the following process is executed in the embodiment.

On the basis of the position of the adhesion member H determined by theadhesion member position determination unit 5 i, the driving of theshaft drive sources 4 k and 4 l is controlled by the shaft control unit5 e such that the adhesion member H is positioned within the detectionrange of the outer diameter detector 4 a, and in this state, the outerdiameter determination unit 5 f determines the diameter at the positionof the adhesion member H in the roll using the result of the outerdiameter detector 4 a.

Alternatively, the following process can be performed. The driving ofthe drive sources 4 k and 4 l is controlled in advance by the shaftcontrol unit 5 e, and the outer diameter for each rotation angleposition of the roll is detected by the outer diameter detector 4 a andstored in the storage area 5 b (hereinafter, the stored outer diameteris referred to as outer diameter data). The outer diameter determinationunit 5 f can determine the outer diameter of the roll on the basis ofthe outer diameter data and the rotation angle position of the rollcorresponding to the position of the adhesion member H determined by theadhesion member position determination unit 5 i, and determine a partialouter diameter of the adhesion member H in the roll by using this outerdiameter as the result of detection from the outer diameter detector 4 ain the state in which the adhesion member H is positioned within thedetection range of the outer diameter detector 4 a.

Further, the movement of the cutter 4 f is not limited to the movementby the rotation, and may be a movement (for example, linear movement) ina posture maintaining a predetermined angle with respect to the sheet.

The urging mechanism 4 j may not be provided in the moving unit 4 b. Forexample, the urging mechanism 4 j may be provided on the base 2 or thesupport mechanism 3. In this case, in a state where the support shaft isdisposed at the splice position, the urging mechanism 4 j can bedisposed at a position where a force can be applied to a portion on theupstream side in the conveyance direction of the sheet based on theguide roll 3 s.

In addition, the example in which the pressing direction (directionalong the detection axis D2) of the pressing roller 4 e is disposedperpendicular to the outer peripheral surface of the standby side rollhas been described, but the pressing direction may not be disposedperpendicular to the outer peripheral surface of the standby side roll(which may be the direction along a straight line that does not passthrough the support shaft in the front view shown in FIG. 12).Specifically, the pressing roller 4 e can be moved up and down.

Note that the specific embodiments described above mainly includeinventions having the following configurations.

In order to solve the above problems, the present invention provides asheet supply device for supplying a sheet from a first roll and a secondroll around which the sheet is wound, the sheet supply device including:a first support shaft that supports the first roll at a center positionthereof; a second support shaft that supports the second roll at acenter position thereof; a joining mechanism that joins the sheet of thesecond roll to the sheet of the first roll; and a controller thatcontrols driving of the joining mechanism such that the sheet of thefirst roll is joined to the sheet of the second roll when a remainingquantity of the sheet of the first roll is equal to or less than apreset remaining quantity in a state in which the sheet of the firstroll is supplied, in which the joining mechanism includes a second shaftdrive source that rotatably drives the second support shaft, an adhesionmember detector that detects a position of an adhesion member providedon an outer peripheral surface of the second roll in a rotationdirection of the second roll, an outer diameter detector that detects anouter diameter of the second roll, and a pressing mechanism that pressesthe sheet of the first roll against the adhesion member of the secondroll, and the controller includes a shaft control unit that controlsdriving of the second shaft drive source such that the second roll isrotated, an adhesion member position determination unit that determinesthe position of the adhesion member in the rotation direction of thesecond roll on the basis of a result of detection from the adhesionmember detector in a state in which the second roll is rotated by theshaft control unit, and an outer diameter determination unit thatdetermines the outer diameter of the second roll in a portion where theadhesion member is positioned on the basis of the result of detectionfrom the outer diameter detector in a state in which the position of theadhesion member determined by the adhesion member position determinationunit is positioned within a detection range of the outer diameterdetector, and the controller controls the driving of the pressingmechanism such that the sheet of the first roll is pressed against theadhesion member of the second roll on the basis of the outer diameter ofthe second roll determined by the outer diameter determination unit.

In addition, the present invention provides a sheet supply method forsupplying a sheet from a first roll and a second roll around which thesheet is wound, the sheet supply method including: a first supply stepof supplying the sheet of the first roll supported at a center positionby a first support shaft; and a joining step of joining the sheet of thesecond roll to the sheet of the first roll using a joining mechanismthat joins the sheet of the second roll to the sheet of the first rollwhen a remaining quantity of the sheet of the first roll is equal to orless than a preset remaining quantity in a state in which the sheet ofthe first roll is supplied, in which the joining mechanism includes asecond shaft drive source that rotatably drives the second supportshaft, an adhesion member detector that detects a position of anadhesion member provided on an outer peripheral surface of the secondroll in a rotation direction of the second roll, an outer diameterdetector that detects an outer diameter of the second roll, and apressing mechanism that presses the sheet of the first roll against theadhesion member of the second roll, and in the joining step, theposition of the adhesion member in the rotation direction of the secondroll is determined on the basis of a result of detection from theadhesion member detector in a state in which the second roll is rotatedby the second shaft drive source, the outer diameter of the second rollin a portion where the adhesion member is positioned is determined onthe basis of the result of detection from the outer shape detector in astate in which the determined position of the adhesion member ispositioned within a detection range of the outer diameter detector, andthe sheet of the first roll is pressed against the adhesion member ofthe second roll by the pressing mechanism on the basis of the determinedouter diameter of the second roll.

In the supply device described in Patent Literature 1, the outerdiameter of the second roll is measured regardless of the position ofthe adhesive tape before the rotation of the second support shaft, andthe pressing position of the sheet of the first roll, that is, theposition of the second roll in the radial direction at the position ofthe adhesive tape cannot be accurately specified.

On the other hand, according to the present invention, the positionwhere the sheet of the first roll is joined to the outer peripheralsurface of the second roll, that is, the outer diameter of the secondroll in the portion where the adhesion member is positioned is detected,and the sheet of the first roll can be pressed against the adhesionmember of the second roll on the basis of the outer diameter.

Therefore, even if the second roll has different outer diameters at eachposition in the rotation direction (even if the second roll is warped),the pressing quantity (distance) of the sheet of the first roll can beset to be a pressing quantity suitable for the position of the adhesionmember in the radial direction.

Therefore, according to the present invention, even if the second rollis warped, the sheet of the first roll can be reliably joined to thesheet of the second roll.

The “adhesion member” includes not only a tape having a base materialand an adhesive layer, but also an adhesive directly applied to a sheetwithout the base material.

Generally, there are plural types of second rolls having different outerdiameters depending on the difference in the length of the sheet woundtherearound. In this case, it is considered to fix the adhesion memberdetector at a position at which the adhesion member detector does notcome into contact with the largest second roll assumed. However, when aroll having a relatively small outer diameter is selected as theactually used second roll, the distance of the adhesion member detectorwith respect to the second roll is long compared with the case where thelargest second roll is selected. Therefore, even in such a case, inorder to reliably detect the adhesion member, there is a problem in thatthe high detection performance is required for the adhesion memberdetector and the cost increases.

Therefore, the sheet supply device further includes a shaft support unitthat supports the second support shaft, a moving unit that supports theadhesion member detector, the moving unit being attached to the shaftsupport unit such that the adhesion member detector is movable between apreset retracted position as a position farthest away from the secondsupport shaft of the second roll in a radial direction and a proximityposition closer to the second support shaft than the retracted positionin the radial direction, and a detector drive source that supplies powerfor relatively moving the adhesion member detector with respect to theshaft support unit to the moving unit, in which it is preferable thatthe controller determines a detectable position where the contact withthe outer peripheral surface of the second roll can be avoided and theadhesion member can be detected, on the basis of the result of detectionfrom the outer diameter detector, and controls the driving of thedetector drive source such that the adhesion member detector moves tothe detectable position when the detectable position is closer to thesecond support shaft than the retracted position.

According to this aspect, it is possible to avoid the contact with thesecond roll by disposing the adhesion member detector at the retractedposition when the second roll having the assumed maximum outer diameteris held on the second support shaft. Moreover, when the second rollhaving an outer diameter smaller than the second roll having the maximumouter diameter is held on the second support shaft, the adhesion memberdetector is disposed at a position (detectable position) closer to thesecond support shaft than the retracted position, and as a result,comparing with the case where the adhesion member detector is fixed tothe retracted position, the position of the adhesion member in therotation direction of the second roll can be accurately detected even ifthe detection performance of the adhesion member detector is low.Thereby, cost can be reduced.

Here, the controller may determine, for example, the outer diameter ofthe second roll at the position of the adhesion member determined on thebasis of the result of detection from the outer diameter detector.However, in this case, when the warpage of the second roll is large andthere is an outer diameter portion larger than the outer diameter of thesecond roll at the position of the adhesion member, it is difficult toreliably avoid the contact of the outer diameter detector with thesecond roll.

Therefore, in the sheet supply device, it is preferable that thecontroller determines outer diameters of the second rolls at a pluralityof locations of the second roll in the rotation direction on the basisof the result of detection from the outer diameter detector in the statein which the second roll is rotated by the shaft control unit,determines an average outer diameter of the second roll on the basis ofthese outer diameters, and determines the detectable position on thebasis of the average outer diameter.

According to this aspect, the detectable position is determined on thebasis of the average outer diameter of the second roll. Therefore, it ispossible to more reliably determine the detectable position at which thecontact of the outer diameter detector with the second roll can beavoided as compared with the case where the detectable position isdetermined based only on the outer diameter of the second roll at theposition of the adhesion member.

Here, when the pressing mechanism has the pressing roller for pressingthe sheet of the first roll against the second roll, the pressing rollerand the adhesion member detector may be supported by differentmechanisms, but in this case, the configuration becomes complicated andthe cost increases.

Therefore, in the sheet supply device, the pressing mechanism preferablyincludes the pressing roller that presses the sheet of the first rollagainst the second roll, the moving unit that supports the pressingroller and the adhesion member detector, and the detector drive source.

According to this aspect, the moving unit can also be used as a supportmember of the pressing roller, and the detector drive source can also beused as the drive source for moving the pressing roller with respect tothe second roller. Therefore, the cost of the sheet supply device can bereduced as compared with the case where the support member and the drivesource are separately provided.

Here, even when the detection axis (for example, in the case of a linesensor, a trajectory through which a midpoint of a detection line fromthe line sensor to an object to be detected passes, and in the case ofan area sensor, a trajectory through which the center of the imagingrange from the area sensor to the object to be detected passes) of theadhesion member detector is not perpendicular to the outer peripheralsurface of the second roll, the adhesion member can be detected.However, in this case, if the outer diameter of the second roll isdifferent, an intersection angle between the detection axis of theadhesion member detector and the outer peripheral surface of the secondroll changes, so the change in the accuracy of detection due to thedifference in the outer diameter of the second roll cannot be avoided.

Further, even when the pressing direction of the pressing roller is notperpendicular to the outer peripheral surface of the second roll, thesheet of the first roll can be pressed against the outer peripheralsurface of the second roll. However, in this case, since the pressingdirection of the pressing roller against the second roll differsaccording to the difference in the outer diameter of the second roll, itis difficult to make the accuracy of joining the sheets according to thechange in the outer diameter constant. Therefore, it is considered thatthe pressing direction of the pressing roller and the detection axis ofthe adhesion member detector are set perpendicular to the outerperipheral surface of the second roll, and the adhesion member detectorand the pressing roller move along the detection axis by the commondrive source.

However, in this case, the adhesion member detector and the pressingroller need to be disposed on a line perpendicular to the center of thesecond roll, and it is not possible to achieve both the improvement inthe accuracy of detection of the adhesion member and the improvement inthe sheet joining accuracy.

In the sheet supply device, the moving unit includes a roller supportmember that supports the pressing roller, and a revolution member thatsupports the adhesion member detector, the revolution member beingrevolvably attached to the roller support member about a rotation shaftparallel with the second support shaft between a detected position atwhich the adhesion member detector is disposed between the pressingroller and the second support shaft such that a detection axis isdisposed perpendicular to the center of the second support shaft and theretracted position where the adhesion member detector is disposed suchthat the distance from the adhesion member detector to the center of thesecond support shaft is longer than the distance from the pressingroller to the center of the second support shaft, and it is preferablethat the moving unit is attached to the shaft support unit such that acenter of the pressing roller is movable in a direction along thedetection axis of the adhesion member detector when the moving unit isdisposed at the detected position.

According to this aspect, since the detection axis can always bemaintained perpendicular to the outer peripheral surface of the secondroll between the retracted position and the proximity position, theaccuracy of detection can be kept constant regardless of the change inthe outer diameter of the second roll.

In addition, by setting the revolution member at the detected position,the adhesion member detector can be disposed between the second supportshaft and the pressing roller to detect the outer diameter of the secondroll. Further, the pressing roller (the sheet of the first roll) can bepressed against the second roll by rotating the revolution member to theretracted position.

Therefore, it is possible to achieve both the improvement in theaccuracy of detection of the adhesion member and the improvement in theaccuracy of joining the sheets.

1. A sheet supply device for supplying a sheet from a first roll and asecond roll around which the sheet is wound, the sheet supply devicecomprising: a first support shaft that supports the first roll at acenter position thereof; a second support shaft that supports the secondroll at a center position thereof; a joining mechanism that joins thesheet of the second roll to the sheet of the first roll; and acontroller that controls driving of the joining mechanism such that thesheet of the first roll is joined to the sheet of the second roll when aremaining quantity of the sheet of the first roll is equal to or lessthan a preset remaining quantity in a state in which the sheet of thefirst roll is supplied, wherein the joining mechanism includes a secondshaft drive source that rotatably drives the second support shaft, anadhesion member detector that detects a position of an adhesion memberprovided on an outer peripheral surface of the second roll in a rotationdirection of the second roll, an outer diameter detector that detects anouter diameter of the second roll, and a pressing mechanism that pressesthe sheet of the first roll against the adhesion member of the secondroll, and the controller includes a shaft control unit that controlsdriving of the second shaft drive source such that the second roll isrotated, an adhesion member position determination unit that determinesthe position of the adhesion member in the rotation direction of thesecond roll on the basis of a result of detection from the adhesionmember detector in a state in which the second roll is rotated by theshaft control unit, and an outer diameter determination unit thatdetermines the outer diameter of the second roll in a portion where theadhesion member is positioned on the basis of the result of detectionfrom the outer diameter detector in a state in which the position of theadhesion member determined by the adhesion member position determinationunit is positioned within a detection range of the outer diameterdetector, and the controller controls the driving of the pressingmechanism such that the sheet of the first roll is pressed against theadhesion member of the second roll on the basis of the outer diameter ofthe second roll determined by the outer diameter determination unit. 2.The sheet supply device according to claim 1, further comprising: ashaft support unit that supports the second support shaft; a moving unitthat supports the adhesion member detector, the moving unit beingattached to the shaft support unit such that the adhesion memberdetector is movable between a preset retracted position as a positionfarthest away from the second support shaft of the second roll in aradial direction and a proximity position closer to the second supportshaft than the retracted position in the radial direction; and adetector drive source that supplies power for relatively moving theadhesion member detector with respect to the shaft support unit to themoving unit, wherein the controller determines a detectable positionwhere contact with the outer peripheral surface of the second roll isavoided and the adhesion member is detected, on the basis of the resultof detection from the outer diameter detector, and controls the drivingof the detector drive source such that the adhesion member detectormoves to the detectable position when the detectable position is closerto the second support shaft than the retracted position.
 3. The sheetsupply device according to claim 2, wherein the controller determinesouter diameters of the second rolls at a plurality of locations of thesecond roll in the rotation direction on the basis of the result ofdetection from the outer diameter detector in the state in which thesecond roll is rotated by the shaft control unit, determines an averageouter diameter of the second roll on the basis of these outer diameters,and determines the detectable position on the basis of the average outerdiameter.
 4. The sheet supply device according to claim 2 or 3, whereinthe pressing mechanism includes a pressing roller that presses the sheetof the first roll against the second roll, the moving unit that supportsthe pressing roller and the adhesion member detector, and the detectordrive source.
 5. The sheet supply device according to claim 4, whereinthe moving unit includes a roller support member that supports thepressing roller, and a revolution member that supports the adhesionmember detector, the revolution member being revolvably attached to theroller support member about a rotation shaft parallel with the secondsupport shaft between a detected position at which the adhesion memberdetector is disposed between the pressing roller and the second supportshaft such that a detection axis is disposed perpendicular to the centerof the second support shaft and the retracted position where theadhesion member detector is disposed such that the distance from theadhesion member detector to the center of the second support shaft islonger than the distance from the pressing roller to the center of thesecond support shaft, and the moving unit is attached to the shaftsupport unit such that a center of the pressing roller is movable in adirection along the detection axis of the adhesion member detector whenthe moving unit is disposed at the detected position.
 6. A sheet supplymethod for supplying a sheet from a first roll and a second roll aroundwhich the sheet is wound, the sheet supply method comprising: a firstsupply step of supplying the sheet of the first roll supported at acenter position by a first support shaft; and a joining step of joiningthe sheet of the second roll to the sheet of the first roll using ajoining mechanism that joins the sheet of the second roll to the sheetof the first roll when a remaining quantity of the sheet of the firstroll is equal to or less than a preset remaining quantity in a state inwhich the sheet of the first roll is supplied, wherein the joiningmechanism includes a second shaft drive source that rotatably drives thesecond support shaft, an adhesion member detector that detects aposition of an adhesion member provided on an outer peripheral surfaceof the second roll in a rotation direction of the second roll, an outerdiameter detector that detects an outer diameter of the second roll, anda pressing mechanism that presses the sheet of the first roll againstthe adhesion member of the second roll, and in the joining step, theposition of the adhesion member in the rotation direction of the secondroll is determined on the basis of a result of detection from theadhesion member detector in a state in which the second roll is rotatedby the second shaft drive source, the outer diameter of the second rollin a portion where the adhesion member is positioned is determined onthe basis of the result of detection from the outer diameter detector ina state in which the determined position of the adhesion member ispositioned within a detection range of the outer diameter detector, andthe sheet of the first roll is pressed against the adhesion member ofthe second roll by the pressing mechanism on the basis of the determinedouter diameter of the second roll.
 7. The sheet supply device accordingto claim 3, wherein the pressing mechanism includes a pressing rollerthat presses the sheet of the first roll against the second roll, themoving unit that supports the pressing roller and the adhesion memberdetector, and the detector drive source.